Over the course of an hour Italian mime Paolo Nani repeats the act of writing a letter. That's it. Not, perhaps, the most promising premise for an evening of hilarity and yet that is exactly what it proves to be.

The Letter is a kind of one-man stand-up mime show. Through a variety of characters and styles, Nani makes a merry pantomime of the business of letter writing. In each vignette the intentions behind the actions, and often the actions themselves, remain the same. The humour is derived from the different ways in which Nani approaches the task: in one routine he is a drunk; in another every little thing takes him by surprise; in yet another he has lost the use of his arms – to name but three examples.

It is a deceptively simple idea and Nani is furiously inventive in the way he exploits these tics and handicaps to comic effect. He is also a great improviser. His mimed contemplation of what could have prompted an audience member to exit from his show is as wicked and funny as any of the rehearsed material.

There is nothing particularly profound to be learnt from The Letter but one will seldom see the comic vocabulary of body language so expertly expounded.