Run, Channel 4

Another week, another breakout performance from Olivia Colman. That chirpy face and sprite smile encourages a nation of fans to follow her into all manner of beastly nooks and dread crannies in the hope that somehow with Colman for company it’ll be all right. Increasingly, it isn’t. After Tyrannosaur (murders husband) and Accused (son murdered) and Broadchurch (investigates child murder), we have Run (sons murder).

Run is running for four nights this week. In the style of The Street, there are several sketchily-linked narratives which tell of lives on society’s pitiless lower rungs where moral choices are not for cissies. Created and written by Marlon Smith and Daniel Fajemisin-Duncan, it promises Lennie James as a recovering heroin addict and Jaime Winstone as a bereaved stripper. But first up was Colman as a single mother, all streaky highlights and estuary vowels. She lives on the type of sink estate in which Mike Leigh’s characters somehow retain their perkiness and mind their language. Not here.

Carol – not that you hear anyone call her that apart from her violent ex who spits the name out like venom – skivvies for two boys in their late teens who have learnt from their old man that it’s OK to walk all over women and, where appropriate, administer a slap or a punch. They’re never in, and if they are it’s for gaming, not meals. A shelf-stacker by day, their mother's only consolation is karaoke with the girls. No sex for Carol: when she hits on a man he advises that she’s off limits – her ex has decreed it. No wonder the empties line up on her bedside table.

One night, her older son is seen haranguing his girlfriend by a foreign passer-by who is promptly beaten to death. The younger brother lends a boot. All too plausibly they pass off the bloodstains as a pub brawl, and Carol ballsily sees the police off her doorstep. But it’s not a front she can keep up and the final moments of her story - grimly staged by director Charles Martin - count the awful cost of giving birth to killers. Colman acts, as ever, without a scrap of vanity to summon a lifetime of crushed hopes and mean emotions from somewhere deep within.

Smith and Fajemisin-Duncan are worth following. Whether the daisychaining of narratives quite comes off is another thing. In the grey area of ethical compromise which is Carol’s world, she’s not above nicking smartphones from the warehouse where she works to sell on to a Chinese dealer (Katie Leung, pictured above, who played the Ravenclaw girl Harry Potter has a crush on), and it’s the story of the illegal immigrant trapped in the black economy Run moves onto next. Don't expect to smile this week.

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