Mike McShane, the slightly slimmed down American comedian and writer, looks as though he’s turning into Timothy West in his own short play about a Kansas car rental worker who skips his job, and his medication, and comes to London to look for the Queen.

He obviously accepts no substitutes; otherwise he could pop round the corner and stalk Nichola McAuliffe in her quirky royal tribute, Maurice’s Jubilee. What’s going on? McShane’s character, Robert James Moore, even visits his doctor clutching a Queen Elizabeth travel bag and sporting a Betty badge.

He tries speed-dating, but all the women – all played by Suki Webster, who’s also the doctor (and Robert’s non-royal romantic nemesis in London) – talk too much. He makes off with a company car. He flies the ocean and heads for St James’s Park. He trains his binoculars on Buckingham Palace.

And before he meets the runaway art student who steals his wallet, then his soul, he gets picked up by a hotel lobby dominatrix (Webster again, this time in torso-crushing black PVC, brandishing a whip). It’s as though Robert is trying out all options and finding them wanting.

It’s a diverting little play, based on the true story of an American weirdo, but it disappears up its own sentimentality, and there aren’t nearly enough jokes or funny moments to send you out satisfied.

It’s good that so many comedians take the plunge and segue into theatre, but Mon Droit is not the first effort to prove that comic drama demands a lot more than confessional-style low-level rambling.