He came blazing out of Glasgow like a rocket, scoring hits and acclaim. As he returns to the stage in a hard-rapping, homoerotic Cyrano de Bergerac, the star talks about partygate, snout size – and tackling Lear when he hits 100

James McAvoy is talking about Cyrano de Bergerac, the long-nosed, lovestruck poet he first played on stage in 2019, and is now about to reprise. But every now and again he interrupts himself with off-piste observations that have nothing to do with 17th-century libertines and doomed love triangles. It slowly becomes clear that he is inside his car, which is parked at the stage door of the Harold Pinter theatre in London, ready to jump into rehearsals after our chat.

“What’s this guy doing?” he says, in his meta commentary of people-watching. “Oh my God. There’s a labourer walking down the road and he doesn’t have any trousers on. He’s just in long johns and he has got the biggest penis I think I’ve ever seen.” Wait, how can he tell? “Because he’s wearing long johns! And he’s packing a nine-inch –”