Black Mirror: The Waldo Moment, Channel 4

After the nightmarish vision of justice system turned spectator sport that was last week’s Black Mirror, you’d be forgiven for feeling a little disappointed that writer Charlie Brooker hadn’t ramped up the horror at the start of the final episode of this all-too-short second series.

There were many adjectives one could consider throwing at Waldo, the inexplicably popular blue cartoon bear at the centre of the action, but “horrific” probably wasn’t one of them.

And yet the climatic moment of this particular piece of drama was the scariest of all, not least because of its sheer plausibility. As he realised that what was once a joke too puerile to properly be called satire had spun a little too far from his control Jamie (Daniel Rigby), the voice of the character, went to launch a projectile at his creation’s giant face. Turning to the crowd, Waldo promised “five hundred quid to the first man to ‘it ‘im”. Predictably, Jamie saw out the results of his experiment from a hospital bed.

 Waldo Moment began with a televised topical sketch show not unlike Brooker’s own Ten O’Clock Live and with the shock resignation of a scandal-embroiled politician not unlike - well, a typical Tuesday afternoon on Twitter. Masquerading as a children’s TV character to give him access to - and the ability to send up - various public figures, Waldo came across as the show’s answer to Jimmy Carr, right down to the knob jokes.

Tobias Menzies was Liam Monroe, the candidate selected by the Conservative Party to contest the safe seat vacated for “a full-time career in the disgraced paedophile industry”. He was also, as luck would have it, a past victim of Waldo’s pranking who didn’t get the joke. It was Monroe’s complaint that brought the character to the attention of the channel bosses who promised a spin-off - which, logically enough, turned into an opportunity to contest the election in character against Monroe. The tale became even more complicated when Jamie, who was insistent throughout about his antipathy towards politics, fell for Labour candidate Gwendolyn Harris (Chloe Pirrie).

Based on recent interviews, Brooker has toyed with the idea of a fictional character running for MP since his Nathan Barley days - but airing less than a year after a man dressed as a penguin won more votes than the Scottish Liberal Democrats in a local council election, this episode struck even closer to the bone than the writer’s typically plausible dystopian visions. The team behind the character brainstormed spinoff media, including a Waldo app that would "unlock" extra catchphrases and a silly hat for the character once the holder voted, and politically-astute viewers realised it was pointless to try to convince themselves that democracy would triumph over X Factor-style gimmicks.

As befits the work of a writer combining several of his passions into one hour of television, there were plenty of priceless scenes in The Waldo Moment. Watching the blue bear rip into a thinly-veiled caricature of Jeremy Paxman on the show’s Newsnight equivalent was the sort of perfectly-pitched comedy moment that will hopefully guarantee another series of this often uncomfortable, but always thought-provoking, drama.