As the series heads towards the end, various story strands start to come together as characters cross plots and meet one another in the latest instalment of Utopia.

Like Episode 3, the star of the episode is actor Neil Maskell, who plays confused killer Arby or, rather, Petrie – as we discovered his real name last week. He and Jessica Hyde’s (Fiona O’Shaughnessy) relationship takes on a whole new twist here with the two making for quite the odd couple and utterly fascinating on screen.

Both so very similar when it comes to killing, and both so very similar in back story. Their scene together in road side cafe was mesmerising as both actors out-weirded one another in performances. Though not in a derogative or gaudy fashion, these portrayals are integral to their dilemma and mistrust.

The revelation, of sorts, that they are brother and sister is well sign posted but is still a kicker, fully fleshing out both killers’ personas. Maskell, in particular, breathes and monotones all over the shop as he sets up his own small apocalypse; one of the most intense characters on television at the moment.

There are more revelations elsewhere, however. Janus is revealed – a plan to sterilise the world’s population (well 90-5% of it). Letts, so brilliantly played by Stephen Rea, calmly informs our heroes of the master plan in a static but shocking scene. To the show’s credit, his argument isn’t totally abhorrent and some may agree that “a thousand million souls starving” is no future for our planet.

As he discusses the end of the Earth’s resources, Letts ponders, “Do you really think we’re just going to share?” He’s got a point, you know. And Wilson is on board. His betrayal of his chums marks an end to the gang’s trust.

Trust is questioned again when the story lines of Dugdale and Ian and co. come together in the final moments. Actor Paul Higgins underplays the Lando-esque treachery superbly and his deception is most definitely curious. Despite his indiscretions, he’d always come across as one of the “good” guys. Seemingly not, though who knows what next week will bring.

It’s a rather cold episode, bereft of humour (which the show does so very well) and warmth but given the seriousness and gravity of the events which take place, it’s hardly surprising. The ending is downbeat, full of a sense of hopelessness and hugely challenging; brave and gripping television.

Aired at 10pm on Tuesday 12 February 2013 on Channel 4.

> Order Series 1 on DVD on Amazon.

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