Review: Operation Mincemeat (New Diorama Theatre)

British artists will make musicals featuring anything these days – the six wives of Henry VIII, F Scott Fitzgerald novellas or even the history of sex toys. So in that sense, theatre company Spitlip's Operation Mincemeat, about an absurd (and very true) World War Two ploy to fool Hitler by using a dead corpse and a dossier full of fake plans, could just be another oddball addition to the collection. But with some show-stopping composition and refined comedy, the show really is an outstanding gem of a concoction.

Spitlip is formed through the pairing of members of the whimsical and whacky fringe theatre favourites Kill the Beast and glam-punk composer Felix Hagan, uniting under one banner to tell the story of messers Cholmondeley (David Cumming) and Montagu (Natasha Hodgson), two members of the wartime secret service coming up with left field schemes to outwit right-wing German fascists. They settle on a plan to fake a pilot's death, in the process "leaking" documents to the Nazis suggesting an imminent (and fictitious) invasion of Sardinia.

By fringe standards this is a long'un, clocking in at over two and a half hours, but the musical flies by with high-kicking verve and vivacity. The stand-out numbers come thick and fast – a beautiful piece of characterisation comes in "Dear Bill", delivered by Jak Malone's heartbroken clerk Hester (reminiscing about a lost love remembered only in his letters), while act one closes with an anarchic earworm of a showstopper in "Let Me Die In Velvet" (as Rory Furey-King notes in the number, "it takes more than the Blitz to stop us puttin' on the ritz"). Hagan pulls out tune after tune, managing to convince even when filling the stage with Nazis goose-stepping to dubstep at the start of act two. A cast recording is, according to the company, imminent.

Operation Mincemeat would sink without its near-incessant humour – every line and tune is mined for its comedic potential (one of the early numbers about dead shrews is especially chortle-some). It would be easy for the show's whimsy to run away from itself, but the cast of five inject enough warmth and authenticity into the veritable trove of different characters to keep the piece grounded.

Special mention must go to Sherry Coenen's lighting design, running in tandem with Dan Balfour's sound to create a sense of scale that extends way beyond the New Diorama's walls. The ensemble's choreography, devised by the company, has all the right amount of pizzazz to make each number unique and distinct while wearing its influences on its sleeve.

The New Diorama has built a year of work out of novel reinterpretations of historical experiences (Orson Wells' famous War of the Worlds broadcast, or the discovery of the first fossils), so Operation Mincemeat feels like a perfect continuation of a trend. Defying both expectations and categorisation, Operation Mincemeat is two acts of glib glamour that glow with theatrical invention and deliver laughs by the gallon. An unmissable end to a stellar season at the north London venue.