There are several excursions down memory lane available for adventurous cinemagoers to explore this week. Despite being personally vetted by Yoko Ono, David Leaf's documentary The US vs John Lennon is anything but a portrait of a victimised saint. It may lack balance, in loading the talking heads with anti-Establishment veterans. But this compelling account of John Lennon's politicisation and his struggle to beat a 1972 extradition order suggests that he was duped by the very people he sought to promote.

By befriending Lennon, Yippie and Black Panther leaders like Abie Hoffmann and Bobby Seale were able to harness his celebrity and media savvy, while also setting him up as a high-profile decoy for the Nixon White House. However, Lennon was so wrapped up in his well-intentioned conviction that he could help change the world that he failed to notice their ulterior motives. Moreover, his delight at being feted for his ideas rather than simply for being a member of the biggest band in rock history seems to have clouded his judgement and prompted him to embrace causes that were occasionally more modish than momentous.

The need to establish the background to Lennon's status in the US requires the rehashing of some overly familiar footage and anecdotage. But the soundtrack is superb and the thesis that Lennon was a naive peacenik whose submersion in his own legend enabled him to be exploited is both original and intriguing.

Lennon made New York his home and the city takes the starring role in Woody Allen's majestic Manhattan (1979). Photographed by Gordon Willis on Technicolor stock that was printed in lustrous black and white, this is not just Allen's most beautiful film, it's also his most heartfelt. Yet, it took the efforts of editor Sandy Morse to dissuade him from disowning a picture that utilises a European arthouse style to expose the pretensions of the Stateside literati.

Caught between enigmatic critic Diane Keaton, vengeful ex-wife Meryl Streep and disarmingly trusting teenager Mariel Hemingway, Allen's TV comedy writer faces his personal and professional crises with typically quotable confusion. But there's a fiercely self-deprecating intelligence behind both the dissection of the academic affectation and the growing awareness that a detachment from life deprives the artist of the ability both to create and to say something worthwhile.

There's more monochrome mastery on show in Pandora's Box (1928), although director G.W.Pabst was accused of betraying Franz Wedekind's source play and compromising his own socio-political convictions by producing this sensual shocker.

Louise Brooks stars as the widow who flees from a Berlin murder trial with her stepson and lesbian companion and drifts into a life of degradation in Jack the Ripper's London. Yet, for all the picture's erotic insinuation and melodramatic intensity, it was also a laudable technical achievement. In addition to blending street realism with French Impressionist and German Expressionist sequences, Pabst cut on movement to bring a new fluidity to the silent visuals. Moreover, he anticipated Josef von Sternberg's tactic of using shadow, smoke and dcor to define space.

But the fascination for most modern viewers lies with Brooks. With her bobbed hair and effortless allure, she delivers one of cinema's most iconic performances. Yet she's almost out-vamped by Jodie Foster in Alan Parker's kitsch musical, Bugsy Malone (1976).

Set in 1929, this is a curious picture, in which Prohibition gangsters and their molls are played by kids. Thirty years ago, it was hailed as a charming piece of pantomime that was no more dangerous than a splurge gun. But some are now comparing its adultilisation of the young cast to the exploitation of the tots on the infamous TV series, Mini Pops. They're wrong to impugn the producers' motives. But it is now difficult to watch this once-amusing romp without grave misgiving.