In acting terms, Michael Caine brings his A-game to this – as does his co-star Aubrey Plaza. And when this script shows us a glimmer of something real and poignantly plausible between them, as it occasionally does, the film comes to life. Sadly though, it is mainly a rather silly high-concept dramedy intercut with maudlin moments, and the sentimental keynote inevitably dominates by the end.

Plaza plays Lucy Stanbridge, the editorial director of a highly unlikely independent publishing house in New York (a little like Meg Ryan’s independent bookstore in You’ve Got Mail) founded by her father and now under financial threat. Desperate to stay profitable, Lucy realises that she is contractually entitled to ask for a new book from the ageing, reclusive and sweary Brit novelist Harris Shaw, played by Caine, a grumpy widower who lives way upstate in a tumbledown house. She chivvies and bullies the adorable old curmudgeon into handing over his new manuscript and going on a book promotion tour – and, of course, his angry, old-fashioned attitude and splenetic outbursts get him a cult following (cue the now outrageously cliched going-viral-on-YouTube montage). Shaw is an old-school writer who doesn’t care about being relatable and building his brand online: he even assaults a sneery critic, played in cameo by Cary Elwes.

There are a couple of quite sweet moments here, with Lucy and Harris actually sharing a motel room on the road and developing a close father-daughter relationship, or rather grandfather-granddaughter relationship, which is complicated when we find out the truth about her dad, and his relationship with Shaw. Mainly the film is silly and unlikely, though, which is a shame because Caine can still bring it. Christopher Nolan gives him great small parts with real bite. Surely someone can offer him a substantial feature role that isn’t sentimental slush?

• Best Sellers is out now on digital platforms.