Bipolar disorder is an ordeal you wouldn’t wish on your worst enemy.

However, general understanding of serious mental illness is murky at best.

Until I watched Being Bipolar (C4, now on 4oD), I had no idea a whopping two million of us Brits have been diagnosed as bipolar (three per cent of the population) – a number that’s rapidly rising.

With this in mind, a Channel 4 film crew followed psychotherapist Phillipa Perry as she met three sufferers to explore its dizzying highs and lows.

First to greet us is Paul – whose excited chuntering about plans to become master of the universe and build a castle where Moses, Putin and the Pope can all come and stay made for viewing more chilling than it sounds.

It later transpires Paul was a multi-millionaire businessman, golf champion and high achiever whose perfectionist standards, along with dabbling in dangerous legal highs, landed him in a lonely world.

Perry’s angle is her interest in life trauma sparking mental illness (“Too often we ask what’s wrong with someone rather than ask what’s happened to them,” she says, reasonably) and helping heal the root causes of this pernicious disorder rather than medicating with psychiatric drugs.

And Perry, with her badger-striped bob and genuine, human warmth, offers a sympathetic approach, especially compared to the disturbing footage of asylum inmates being wired up to electroshock treatment in the bad old days.

Next, she meets Sian – a thoroughly ‘normal’ mum in south Wales, describing her interludes of glorious technicolour in absorbing detail, followed by the equivalent depths she plunges to.

Despite her brave smile, this is a woman who has been wracked by guilt over the plight of her children. Whether they will inherit her problems is a constant, haunting question mark and she has became so desperate she has attempted suicide three times in the last year.

The final interviewee is Ashley – a 36-year-old musician whose life is spent surviving a rollercoaster of euphoric highs and crushing lows, taunted by an ever-present dialogue.

Anyone unaffected by bipolar disorder might ponder how people could end up being such slaves to their emotions.

This programme is must-see viewing to make you feel grateful for what fragments of your own mental health remain ‘sane’ (whatever that is) and compassionate to those still going through hell.

Sometimes labels do not cover the Pandora’s box of symptoms contained (Ashley is also on the autistic spectrum, and hard to reach – there is no quick fix in life). However, even though Perry’s theory about trauma as the source of bipolar might not hold true, her approach of kindness is joyfully justified by Sian, who looks as though the weight of the world has been lifted from her shoulders by the closing credits.

Poor Jon Snow. You might have seen him valiantly posing with a spliff during the hype around C4’s Cannabis: Live last week, but those who tuned in expecting a big marshmallow hug of a show will have found twitchiness and paranoia rolled into one.

C4’s aim was to explore the role of hash and skunk on the brain, during a surreal live show spliced with VTs of random telly celebs getting stoned. Jennie Bond and Matthew Parris showed signs of giggly, if amnesiac, pleasure but the footage of Snow crumpled into a sobbing panic attack (after being shoved into an MRI scanner, natch) talking about his soul being ripped out, was disturbing. Luckily, a scientist was on hand to give him a cuddle, but that seemed a bit lame after a series of experiments seemingly engineered to stoke The Fear.

Dr Christian Jessen was on intense, fidgety form as he buzzed around the studio, quizzing stoners and Richard Branson on their experiences and could, really, have done with chilling out.

The hazy conclusion was that draconian drugs laws have resulted in the market being flooded with skunk, which is a hell of a lot more volatile and dangerous than its 1960s counterpart. Next to a giant plastic brain, under the glare of studio lights and 16million eyes, unsurprisingly, the show did not offer the relaxed vibe many viewers might have tuned in for.