The long-time character actor gets her first lead role in this confident, twisty witness protection thriller. She gives it everything – even if you sense she deserves more of a challenge

Always and forever when I see Siobhan Finneran on screen I am catapulted back nearly 40 years to her mardy teen outrage in the 1987 film Rita, Sue and Bob Too as she objects to Sue always going first when they are out shagging Bob in his car on the moors. “It’s not so good, t’second time!” It’s the funniest, bleakest thing you’ll ever see.

Finneran has worked consistently ever since, but in recent years she has really come into her kingdom as a brilliant character actor – the woman you go to when you need someone to play a marrow-deep weariness with the world. Most notably this has been employed by Sally Wainwright in Happy Valley, in which Finneran played Sgt Catherine Cawood’s struggling, vulnerable, recovering/lapsing addict sister, Clare, smashing Catherine’s and viewers’ hearts into pieces at several points along the way, before we all gamely picked ourselves up and carried on, as Finneran’s characters tend to do.