For years, Richard Curtis has attracted imitators to his brand of upscale London romcom. This squelchingly sub-Curtis effort is a case in point, and what’s so baffling is that it is co-written by Emma Thompson, whose undoubted screenplay skills form part of her unique double-Oscar achievement (one for acting in Howards End, the other for adapting Sense and Sensibility). And it is directed by the equally estimable Paul Feig, who gave us Bridesmaids and the Ghostbusters remake.

This grisly Christmassy adventure features unbearable skittery-giggly dialogue of the sort not spoken by actual humans, while it attempts to siphon off the eggnog flavour from Curtis’s Love Actually, with a female lead who is a Frankenstein’s-monster mix of Bridget Jones and the quirky sister from Notting Hill. The film is supposedly inspired by the music of the late George Michael – who gave his permission some years ago – and when the connection between the twist reveal and Michael’s lyrics dawns on you, there is a real danger of you going into anaphylactic shock. Suffice it to say that this reveal is a time-honoured conceit that has featured in a number of films, some by very grand directors. But the weird thing is that Michael’s music and personality do not feature all that much.

Emilia Clarke (Daenerys Targaryen from Game of Thrones) plays Kate, a wannabe singer who has a terrible day job working in a Christmas store, selling baubles while humiliatingly dressed as an elf; her manager is a woman calling herself Santa, played by Michelle Yeoh. Kate has a number of private problems, including a tricky relationship with her Croatian mum, played by Thompson. Then she meets dishy but enigmatic Tom, played by Henry Golding, and her life seems as if it is about to change.

There is some heart-in-the-right-place material about Brexit and bigots on the bus, and Last Christmas arguably deserves points for being one of the very few, or perhaps the only mainstream film to talk about Brexit. But everything about this clunks.

• Last Christmas is released in the UK on 15 November.