Mr Swallow - Houdini, Soho Theatre

Nick Mohammed doesn't do things by halves as his chatty airhead alter ego Mr Swallow. Forget the scholarly approach of finely researched biographies of Harry Houdini (“boring!”); his “first-ever entirely true auto-biopic” of the magician and escapologist comes complete with conjuring tricks, song-and-dance numbers and a whole lot of laughs.

Ably assisted by David Elms as Mr Goldsworth and Kieran Hodgson as Jonathan (in oriental tunics for no discernible reason), plus an onstage pianist, Mr Swallow chatters on, while Mr Goldsworth, the producer of this show within a show, has a devil of a job trying to keep the easily distracted and lazily under-rehearsed Mr Swallow (his attempts at accents are particularly memorable) focused on Houdini's life story. He prattles away about any insignificant or irrelevant detail that comes into his head, and breaks the fourth wall with abandon. “I could murder a Schloer,” he says, fanning himself, after one exerting scene, his lispy and camp demeanour making the joke even funnier.

Will Mr Swallow escape from a padlocked water tank while in handcuffs?

But while the Houdini biographical details may be in short supply (and of questionable veracity in a giddily funny seance scene), Mr Swallow actually does perform some kosher conjuring tricks. We may be expecting Tommy Cooper-style deliberate fluffs but he can do them for real (like Cooper, Mohammed is a member of the Magic Circle), and we are as surprised as Mr Swallow is when the tricks come off.

But trained magician or not, when it comes to using the water tank on stage (apart from it being where watermelons, conjured in other magic tricks, end up), Mr Swallow is having none of it. “Oh, piss off! No! No way!” he explodes when Mr Goldsworth tells him its purpose. In a show that already works on so many levels, this gag takes it even deeper: is this the cowardly Mr Swallow talking, or Mohammed, who's not that game for a laugh, or even Houdini himself, who knows a dangerous trick when he sees it?

The show, like the tricks, is tightly constructed, and even a scene that appears to go into freefall is anything but. When Houdini and his wife visit the doctor, a simple story point unravels hysterically before us as Mr Swallow, moving in and out of character even mid-sentence, tries to argue his way of out performing Houdini's death-defying stunts. It deftly combines visual jokes, throwaway gags and physical comedy.

The finale, too, is expertly built – will Mr Swallow really re-enact Houdini's most famous trick and escape from a padlocked water tank while in handcuffs? – and there's real tension in the room. You'll have to see the show itself for all its daft, escapist fun, and all I'll say is that Nick Mohammed is alive and well.

• Mr Swallow – Houdini is at Soho Theatre, London W1 until 18 February

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