Two things are readily evident this week. Firstly, the country's film distributors have taken evasive action in deciding not to release anything of major significance opposite the summer's biggest blockbuster, The Dark Knight Rises. Secondly, the Olympics are now only seven days away, as why else would a rather self-indulgent documentary about two men travelling from Hastings to Hackney in a swan-shaped pedalo be the pick of the week?

In 1996, Andrew Kötting took his 85 year-old grandmother Gladys and his seven year-old daughter Eden on a tour of the British coastline in Gallivant. The seaside also provides the starting point for his latest odyssey, Swandown, as he and writer Iain Sinclair launch a white plastic craft from a Sussex beach in order to celebrate the passing landscape and the eccentricity of its populace over the course of some 160 miles. The idea was that the pair would learn much about their environs and themselves during an undertaking that would exploit Kötting's quirkiness and Sinclair's loquacity. But, despite some memorable images and the occasional amusing encounter, this `dada performance' never quite lives up to expectations and, like many a home movie before it, was probably more fun to make than it is to watch.

Having vowed to meld their souls with that of Edith, the craft unchained from her moorings by night and named after the swan-necked mistress of King Harold Godwinson, the pair declare themselves via a walkie-walkie link to be `flesh radios', who will transmit and receive signals along the route. They look incredibly vulnerable as they struggle through choppy seas and it comes as something of a relief when they reach calmer waters at Rye. Accompanied by the commentary from an old travelogue, they turn inland and are shown a photograph of themselves fighting the tides by a fisherman, who thought they must have been kids who had stolen the swan as a prank.

Indeed, a sense of mischief informs the entire enterprise, with Kötting referencing The African Queen (1951) as he pushes the pedalo through silted shallows, while the screen associations are further reinforced by clips from the soundtrack of Les Blank's documentary Burden of Dreams, in which Werner Herzog recalls the tribulations he endured during the making of another unconventional nautical excursion, Fitzcarraldo (1982).

Just past Bodiam Castle, Kötting has Kristin O'Donnell recreate John Everett Millais's famous Pre-Raphaelite painting of the drowning of Ophelia before allowing Alan Moore and Stewart Lee - respectively described as `Writer and Prophet' and `Writer and Clown' - to take over pedalling duties at Tonbridge. The newcomers gamely attempt to ascribe some deep philosophical meaning to the quest, but end up contenting themselves by joking how pedalo propulsion would be the ultimate inter-faith Olympic sport, as it would be impossible to hate anyone with whom one had spent any time in such close proximity.

On reaching the Medway, Kötting and Sinclair get a mixed reception from those aboard pleasure craft that deflect them with their wash. But they enjoy a natter with a man explaining how he celebrated the birth of each of his five children with a new tattoo before Kötting and Dr Mark Lythgoe ruminate upon Karl Popper's thesis that scientific investigation should always search for the single black swan that proves the exception rather than being led by experience and presuming that all such birds must be white.

Once Sinclair has resumed his seat, the duo launch a model version of Edith, which they dub Sitwell and shortly afterwards honour Dame Edith by clambering up a tree to recite `Hornpipe' from her Façade series of poems. The lyrical bent continues under cover of darkness, as Sinclair compares the candles lighting their way with the glow of souls seen by those crossing to the other side. However, Dudley Sutton (billed as `Gargoyle & Actor') deflates the mood with a coarse poem about old age and not even the later efforts of `Orator & Artist' Marcia Farquhar to declaim something from WB Yeats's `Leda and the Swan' can recapture it (especially when she protests volubly about being branded a `pedalphile').

As they pass through Maidstone (near where Kötting grew up in Chislehurst), Sinclair begins to complain about the grasping reach of the false and corrupt entity that is London. A time-lapse sequence speeds them on their way and camera engineer Anonymous Bosch and soundsmith Jem Finer take their turn alongside Kötting, as he navigates beneath soulless concrete monstrosities that contrast starkly with the charming medieval stone bridges seen further downstream.

Sinclair resumes his place at Rochester and they glide past giant boats moored at jetties and discuss the extent to which Charles Dickens caught the atmosphere of the marshes with which they are about to become better acquainted, as they are forced to pull Edith along on a trolley (at one point parodying the `Dance of Death' sequences from Ingmar Bergman's 1957 masterpiece, The Seventh Seal). Kötting is also warned by a man on the bank that he should avoid getting dirty water in a rat bite on his shin. But they carry on regardless to Sheerness and the Isle of Grain, where they follow a nocturnal bonfire with a paean to the tidal waters of the Thames from Sinclair's own book, Downriver.

However, he is soon to depart for Boston and spends the last stretch after Dartford Bridge on a vessel named Endurance before disembarking for the final time near the Millennium Dome. As a vehement opponent of the Olympics and the damage it has done to the Lower Lea Valley (a theme to which he would return in Daniele Rugo's actuality The Olympic Side of London), Sinclair clearly isn't too distressed at missing the last leg. Indeed, it makes for rather desultory viewing, as Kötting passes through polluted waters hemmed in by graffiti-strewn walls and comes to a nugatory halt against a yellow chain barrier within sight of Peter Cook's stadium. The minor security alert he causes proves equally anti-climactic and the picture ends with Kötting lamenting Sinclair's absence, as he, Edith and Sitwell swirl gently in the eddies of a filling lock.

Filmed over four weeks during September and October last year and intercut with audiovisual snippets from a typically eclectic range of literary, filmic and recorded sources, this droll, but frequently meandering diversion could only have been made by Andrew Kötting (who first collaborated with Sinclair on Offshore, his 2007 account of a swim across the Channel). As always, a faint whiff of pretension pervades proceedings that Sinclair avers is `a blend of Benny Hill, Stan Brakhage and Joseph Beuys'.

But, such is the overriding playfulness, that, even at its most frustrating, this is impossible to dislike. It also contains moments of sublime beauty, most notably when morning mists lay low over the riverbanks, while Sinclair periodically tries to introduce a valiant note of psychogeographical provocation. However, the guest slots are largely a miscalculation and one is left wondering about the quality of discarded contributions by the likes of artist Dinos Chapman if these were the best. Nevertheless, this genial peregrination consistently delights and, in cleaving closer to Jerome K. Jerome's best-known novel than to Joseph Conrad's Heart of Darkness, it succeeds in compelling the audience to think again about the social, economic and environmental effects of hosting the greatest sporting show on earth.

Ryan O'Nan plumps for a more traditional form of cinematic picaresque in his debut feature, The Brooklyn Brothers Beat the Best, a musical road movie that is just offbeat enough to become a cult favourite. Admittedly, things get off to a sketchy start and it's easy to see why one critic deemed this a laddish hybrid of Little Miss Sunshine and Flight of the Conchords. But once it hits the highway and the catchy tunes and oddball characters begin to cast their spell, the action gathers amusing momentum until it reaches its anticipated, but nonetheless desirous destination.

Kicked out of a two-man band by Jason Ritter because he doesn't have sufficient first-hand experience to write convincing songs about vampires and demons, Ryan O'Nan loses his job in a real estate agency when boss Christopher McDonald fires him for beaning smart alec co-worker Wilmer Valderrama with a water cooler bottle. He is even prevented from performing for special needs kids (while dressed in a moose suit) after he pulps the child who attacked him with a toy knife. Thus, with his girlfriend dumping him and his prospects seeming to be careening towards a dead end, O'Nan reluctantly agrees to go on a cross-country tour with Michael Weston, a singular musician who lives with grouchy grandfather Douglas Watson and plays a bizarre range of plastic instruments, as well as the keyboards.

Although encouraged by the pleasingly distinctive sound they achieve while jamming on the road, O'Nan is less enamoured when Arielle Kebbel, the promoter of their debut gig, decides to tag along for the ride. However, he is grateful for her presence when Weston gets drunk out of sheer relief when furious Tennessee club owner Charle Chu buys his excuse as to why Scott Weiland of the Stone Temple Pilots is not going to sit in with them. But it's only after they prove an unexpected hit at a college frat party that O'Nan and Kebbel finally tumble into bed together - only for him to wake next morning to find her gone with all their remaining cash.

Out of fuel and increasingly low on patience, O'Nan helps Weston push the car along. But he quits after an exhausting afternoon chopping wood for petrol money and heads off to stay with Andrew McCarthy, the God-fearing older brother who raised him after their parents died and who continues to support him, despite disapprovingly wholly of his lifestyle. Indeed, he even forgives O'Nan for waking him in the middle of the night while writing a song about monsters with his 10 year-old nephew Jake Miller and even overlooks his insulting behaviour in front of ultra-conservative neighbour Melissa Leo. Moreover, when Kebbel arrives out of the blue to inform O'Nan that Weston has gone to Los Angeles alone to enter a Battle of the Bands competition at a notoriously violent venue, McCarthy gives his sibling a lift so that he can finally find what he has been looking for.

With its anecdotes about genital-nipping dogs and numerous musical interludes, this variation on the Hope/Crosby/Lamour `Road' scenario occasionally tries too hard to be kooky. The first third is particularly unappealing, as O'Nan clumsily piles on implausible disasters in pitching his protagonist to rock bottom. But, once he hooks up with Weston and Kebbel, the goofiness becomes more congenial, while there is genuine poignancy in the scenes he shares with McCarthy and Miller. It remains unlikely that songs making such capriciously idiosyncratic use of toy melodicas, accordions and xylophones would be so enthusiastically received by such diverse audiences. But this is a minor complaint about a comedy that has just enough charm to atone for its moments of vainglory and venality.

Just as O'Nan's debut starts shakily, so Lola Doillon's sophomore outing, In Your Hands, has serious trouble ending. Changing tack dramatically from her 2007 teen saga, Just About Love, Doillon is so intent on creating a thriller in the mould of Guillaume Canet's Tell No One (2006) and Philippe Claudel's I've Loved You So Long (2008) that even she hired their female star, Kristin Scott Thomas. However, in attempting to bookend a prolonged flashback with consequent action, Doillon dissipates all tension before arriving at a denouement that is not only melodramatic, but also deeply flawed.

As the story opens, obstetrician Kristin Scott Thomas leaves a nondescript house in the Parisian suburbs and rushes to a nearby garage. She attempts to return to work, as though nothing had happened, but finds it impossible to forget her ordeal. Indeed, she is contemplating reporting the matter to the police when Doillon takes us back to her abduction at knife-point by Pio Marmaï, a grief-stricken widower who is out to avenge his wife's death, two years earlier, when Scott Thomas had attempted to carry out an emergency caesarian.

Unable to bear living with the daughter who is now being raised by her grandmother, Marmaï keeps his captive in a windowless basement room with a rickety iron bed and makes no attempt to communicate as he delivers her meagre meals. However, as the days go by and Scott Thomas becomes increasingly convinced that, despite his hissed threats and occasional fist-flailing outbursts, Marmaï is not going to hurt her, she tries to lure him into a conversation to ascertain why she is being held. Yet, while she gains his trust, she keeps looking for opportunities to escape and it's only when she is free that she comes to appreciate the agony he has experienced since his wife's death.

Driven by the memory of the sexual frisson she had felt in his presence, the divorced and childless Scott Thomas begins to stalk Marmaï and eventually brings him back to her apartment, where they sleep together. However, she is overcome with disgust at giving herself to a man who had caused her so much distress. Yet, even after she betrays him to the police, Scott Thomas still feels compelled to try and warn him and there is palpable pain in the glance they exchange as Marmaï is led away.

Doillon (who is the daughter and wife of acclaimed directors Jacques Doillon and Cédric Klapisch) stuffs this treatise on the Stockholm Syndrome with simmering Freudian symbolism about mother-son relationships. She is superbly served by leads who each feels themself to be the victim and whose respective transition from fear and fury to fervour is credibly done. However, the action becomes increasingly implausible once Scott Thomas begins pursuing Marmaï and their climactic coupling and separation smacks of soap operatics.

With Mathieu Vadepied's camera largely being confined within Stéphanie Guitard and Stanislas Reydellet's forbiddingly claustrophobic set, this might have been better suited to the stage than the screen. But, even there, the problem of the resolution would remain, as it did in another recent Scott Thomas vehicle, Pawel Pawlikowki's The Woman in the Fifth.

The estimable Scott Thomas has been able to sustain successful careers in France, Britain and Hollywood. Yet, as Pete McCormack reveals in the documentary I Am Bruce Lee, the undisputed king of martial art movies struggled to find a niche in the United States and frequently had to return to Hong Kong in order to finance his films and ensure a modicum of creative freedom. Having received an Oscar nomination for his 2010 short, Facing Ali, McCormack clearly knows a bit about the fight game. He also understands how a warrior can become a politico-cultural icon to repressed people. But this is such a hagiographical account of Lee's life and legacy that it is almost unwatchable for anyone but fanboys.

Often strewing the screen with Godardian captions highlighting phrases from the numerous talking-head paeans to Lee's genius as both a fighter and a philosopher, McCormack edits to the pumping rhythms of an omnipresent soundtrack that consistently makes this feel much more like a tele-product than a big-screen study. His use of a monochrome interview that Lee did in Hong Kong with Pierre Berton in December 1971 is adroit, especially as it provides keen insights into his theories, techniques and personality. But, with other contributions ranging from the earnestly admiring to the besottedly devoted, this actuality offers little by way of objective analysis of Lee's abilities as a either martial artist or a film star.

Born Lee Jun-fan in San Francisco in 1940, Lee was raised in Hong Kong, where his father, Lee Hoi-chuen, was a leading Cantonese film and opera star. Having survived the Japanese occupation, he became a minor child star in pictures like Feng Feng's The Kid (1950). Yet, despite his privileged position, Lee drifted into street fights as a teenager and his parents entrusted him to Yip Man to learn the skills of Wing Chun. Lee also excelled at the cha-cha-cha and won the national championship in 1958. However, he kept getting into trouble and, the following year, he was dispatched to the United States with just $100 in his pocket.

Settling in Seattle, Lee enrolled at the University of Washington and married Linda Emery (at a time when mixed-race marriages were frowned upon). He also began teaching his own brand of Wing Chun, known as Jun Fan Gung Fu, which evolved into Jeet Kune Do after Lee relocated to Oakland and made his first US screen appearance as the chauffeur Kato in the cult TV series The Green Hornet (1966-67). Influenced as much by boxing and fencing as traditional martial arts, this `style of no style' gained notoriety after a demonstration at the 1964 Long Beach International Karate Championships led to a private duel with Wong Jack Man (who favoured the Xingyiquan) to determine whether Lee would be permitted to teach non-Asian students. He won and later counted James Coburn, Steve McQueen and Roman Polanski among his disciples.

The latter's tragic involvement in the Manson murders is mentioned in passing, as is Lee's home life as the father of Brandon and Shannon. But McCormack is much more interested in Lee the Legend than the family man and, thus, he lets the picture be hijacked at this juncture by a discussion of whether Lee (who stood 5'7" and weighed 135 lb) was a genuine tough guy and the founder of Mixed Martial Arts, which, along with the Brazilian Vale Tudo, forms the basis of the Ultimate Fighting Championship style that is currently so popular.

UFC President Dana White and fighters Stephan Bonnar, Gina Carano, Jon Jones and Cung Le pitch in their ten pennyworth along with martial artists Daniele Bolelli, Teri Tom and Diana Lee Inosanto, boxers Ray 'Boom Boom' Mancini and Manny Pacquiao, basketball star Kobe Bryant, skateboarder Paul Rodriguez, dancer Jose Ruiz, actor Mickey Rourke, director Reginald Hudlin and Black-Eyed Peas member, Taboo. It all gets a bit heated, especially when Gene LeBell insists that he is the real originator of MMA and fellow Lee movie stuntman Robert Wall, actor Ed O'Neill, longtime Lee associates Richard Bustillo and Dan Inosanto and authors Paul Bowman and David Tadman are called upon to restore order. Sadly, the debate is somewhat unedifying and suggests the documentary exists more to perpetuate Lee's mythology than explain his unique talents and enduring appeal.

The narrative gets back on track, however, as McCormack recalls Lee's abortive bid to team in 1969 with James Coburn and screenwriter Stirling Silliphant on a feature entitled The Silent Flute, as well as his failure to persuade Warner Bros to back The Warrior, the story of a Shaolin monk in the Wild West that many consider to have been the forerunner of the long-running series, Kung Fu. Instead, Lee followed the advice of producer Fred Weintraub and returned to Hong Kong to sign with Raymond Chow at Golden Harvest and make The Big Boss (1971) and Fist of Fury (1972) with director Lo Wei.

Something of a perfectionist, Lee insisted on writing, directing, starring and choreographing Way of the Dragon (1972), which pitted him against Chuck Norris. However, while he was shooting Game of Death (1972) with basketball giant Kareem Abdul-Jabbar, Lee was offered the chance to headline Robert Clouse's Warner-backed  Enter the Dragon (1973), which remains his most iconic picture. Made for just $850,000, it has since grossed around $200 million worldwide. But its status owes much to the fact that the 32 year-old Lee died before its premiere and McCormack wisely allows widow Linda Lee Cadwell to dismiss the various conspiracy theories about curses and triad contracts before reaffirming her belief in Lee's decency as a husband and genius as a martial and movie artist.

Lee certainly comes across as a captivating character in the Berton interview and McCormack might have been better advised to stick to the recollections of family members and close friends rather than clutter proceedings with cliché-spouting acolytes. His speculation about how Lee would fit into the contemporary cinematic and fight scenes is also of less value than a considered assessment of Lee's battles against racism and the fact that he became such a superstar on the basis of only four completed features. Thus, with a lot less hyperbole and a touch more impartiality, this might have satisfied the die-hards while also doing more to convince the sceptics that there is more to Bruce Lee than the myth and the merchandising.

Non-aficionados are also going to struggle to get much out of Ice-T's Something From Nothing: The Art of Rap, as it follows the gangsta legend on an odyssey across the United States to chew the fat with fellow rappers and MCs and afford them the opportunity to bust the odd rhyme. Essentially an exercise in back-slapping mutual admiration, this will disappoint those seeking an introduction to hip hop's social history, musical context and cultural significance. Moreover, many fans are inevitably going to bemoan the omission of their particular favourite. But, given how little attention American cinema has paid to rap over the last three decades, one should be grateful that Ice-T has managed to coax so many big names into sharing their secrets and memories.

For the record, the marquee talent that Ice-T meets on bustling street corners and inside soulless studios are Afrika Bambaataa (Planet Rock), Melle Mel (Grandmaster Flash and the Furious Five), Chuck D (from Public Enemy), Run and DMC (of Run-DMC fame), B-Real (Cypress Hill), old skooler Grandmaster Caz, Big Daddy Kane (Juice Crew), Raekwon (Wu-Tung Clan), human beat box Doug E. Fresh, Treach (Naughty By Nature), Ras Kasss (HRSMN), epochal producers Dr Dre and Marley Marl, white superstar Eminem, Ice Cube (NWA), Snoop Dogg, Kanye West and Yasiin, who is better known by his stage name, Mos Def.

He also catches up with female rappers Cheryl `Salt' James (of Salt-n-Pepa) and MC Lyte, as well as such less familiar performers (at least to this critic) as Bun B, Chino XL, Common, Dana Dane, DJ Premier, Immortal Technique, Joe Budden, Kool Keith, Kool Moe Dee, KRS One, Lord Finesse, Lord Jamar, Nas, Q-Tip, Rakim, Redman, Royce Da 5'9", WC and Xzibit. Yet, for all their bravado and bluster, few have anything revelatory to say about the supposed four pillars of hip hop: DJing, MCing, B-boying and graffiti tagging.

Indeed, what is so surprising, considering the intricacy and complexity of their work, is how inarticulate the majority of the rappers are when asked to recall their influences, define their style or reveal how they compose their stuff. Ice-T himself is hardly a natural interviewer, but he elicits `dope' anecdotes from Melle Mel, Grandmaster Caz, Eminem, KRS One and Snoop Dogg and affords the rest the latitude to spit out their a cappella lyrics with suitable panache. But the narration is often as banal as the visuals, which make excessive use of aerial shots over the New York and Los Angeles neighbourhoods that begat hip hop. Then again, this wasn't produced with 51 year-old Beatle fanatics in mind. So it's best to quit while ahead and concede that this will be lapped up by its target audience.

Finally, one suspects that Chris Paine's Revenge of the Electric Car will also have a limited appeal, as this sequel to the 2006 documentary Who Killed the Electric Car? lacks both the macho motor porn element that would recommend it to viewers of Top Gear and the intellectual rigour that would entice eco activists keen to assess how the American automotive industry is responding to the challenge of manufacturing viable hybrid or all-electric vehicles before the inevitable and increasingly imminent post-oil crisis arrives. Moreover, despite Thaddeus Wadleigh's acutely observed imagery and Chris Peterson's slick editing, it desperately misses the conspiracy aspect that made the original so compelling. But what is most dismaying about this markedly less combative follow-up is the emphasis that Paine places on personality over the more pressing industrial and environmental issues at stake.

Having been presented as the villain of the first piece for his role in the collapse of the EV1 project, General Motors Vice Chairman Bob Lutz is given a much easier ride as he seeks to promote the Chevrolet Volt, an electric car that comes with a back-up gas-powered engine as standard. Schmoozing Paine on his luxury estate, he admits to past mistakes and claims to be `an environmentalist, within limits' in eulogising the new product's long-range capabilities.

Nissan  CEO Carlos Ghosn agrees that the future is electric and he sells the Japanese behemoth's all-electric Leaf with the zeal of an old-time medicine show barker. Dot.com millionaire Elon Musk (the founder of PayPal) is equally effusive in promoting the Tesla, a roadster named after the inventor Nikola Tesla that is designed to corner the higher end of the market. However, with a private space programme also demanding his attention, Musk struggles to cope with the production problems that arise just as the US economy comes close to meltdown.

By contrast, Greg `Gadget' Adams gets by converting gas guzzlers his California workshop. Yet even his modest zero-emission business is beset with problems and Paine is left to wonder whether the green revolution is ever going to happen. But rather than pursuing this salient point, the Tim Robbins-narrated documentary allows itself to get distracted by guest appearances by Arnold Schwarzenegger, Adrian Grenier, Jon Favreau and Danny DeVito, who all claim an enthusiasm for alternative autos.

It's only when the October 2008 slump descends that minds are refocused and Paine kicks the celebrity obsession to return to the central theme of his quest. Over the next few months, Ghosn alone sticks to his game plan, while Lutz is forced to go cap in hand to Washington for a GM bailout, Musk risks ruin by pressing ahead with his Preston Tucker-like dream at the very time he is negotiating a divorce settlement and Adams has to deal with both the blaze that destroys his Custom Cars facility (and the uninsured vehicles on which he was working) and the discovery that his replacement site in Los Angeles's Chinatown has a mercury contamination.

As a result of these sudden changes in fortune, Paine stumbles across the vision, acumen and tenacity that makes his very different subjects so remarkable. Indeed, this accident of being in the right place at the right time not only gives the film some much-needed momentum, but also a sense of direction. Ultimately, each member of the quartet seems to have overcome the bumps in the road and a closing caption predicts that there will be one million electric cars traversing US highways by 2015. But quite whether this constitutes the `revenge' that the title avers is another matter.