There’s embellishing a dating app profile. And then there’s creating an entirely fictitious persona. But for dapper charmer Roy Courtnay (Ian McKellen), a grizzled grifter and veteran conman, lying is a way of life. When he meets well-heeled widow Betty McLeish (Helen Mirren), he settles comfortably into her suburban lifestyle, a world of polite pastels that he privately describes as like being “smothered in beige”. Betty, meanwhile, seems determined to grasp late-life happiness with Roy, despite the reservations of her grandson Steven (Russell Tovey).

Adapted by Jeffrey Hatcher from a novel by Nicholas Searle, The Good Liar is at its sparky best when Mirren and McKellen are on screen, waltzing smoothly through a plot that feels like a Russian doll of deeper and deeper deceptions. Flashes of violence are effectively jarring when juxtaposed with the chintzy cosiness of much of the film. Less successful are two thudding, lead-weight flashbacks, which disgorge chunks of exposition and quash some of the fun in McKellen and Mirren’s deft double act.