It takes an Irish actor banished to remotest Cornwall in childhood to cook up a monologue as witty and fanciful as this. Gurning, posturing and doing all the voices, Ed Gaughan teleports around American history, Dr Who style.

Narrating as a lugubrious coach driver on an all-night trip from Penzance to the city he calls “up‑London”, Ed introduces us to a transatlantic world of crooked businessmen, out-and-out gangsters, political refugees, worried mothers, mad scientists and jazz geniuses.

Fact mingles with fiction as we follow his IRA antecedents’ escape to America in the hungry Thirties, in time to witness the birth of live-music radio from Macy’s department store in New York. There’s also some business involving Doctor Scientist, a central European professor with metaphysical answers to such questions as What Is Music?

The writing, by Gaughan, Andrew Buckley and director Wes Williams, is sharp and studded with in-jokes. Studying test tubes labelled “Essence of Ella Fitzgerald” or “Chet Baker”, the Prof sips the wrong one. “Tcha!” he splutters, “Jamie Cullum!”

Occasionally the wordplay is as thought-provoking as good theatre should be, and the jazz trio on stage is a real bonus: it’s a pleasure to hear Christine Tobin singing standards again, while guitarist Phil Robson is his usual brilliant self.

Ends 25 October. Information: 0870 0500 511.