Jessie Nelson (book) and Sara Bareilles’ (music and lyrics) musical tragicomedy Waitress, based on Adrienne Shelly’s film and currently entering its fourth year on Broadway, comes to the West End with one of its former New York leading ladies, Katharine McPhee, in the title role. Jenna is one of the waitresses at a small-town diner that specialises in pies, but she’s also the cook who bakes them, and comes up with a new flavour invention every day to be the daily special. She themes these around her moods and preoccupations of the day, so ends up with flavours like blueberry and bacon, or marshmallow and mermaid (?) pie that have become the diner’s signature dish. At the start of the show she’s devastated to discover that she’s pregnant – and that it is her husband Earl’s (Peter Hannah) baby.