Nick Mohammed, Pleasance Courtyard, Edinburgh

How to define Nick Mohammed’s show? It’s a character comedy/maths lecture/magic show with a bit of Countdown and some acrobatics (he does an Arab spring – and has been doing them since way before the political movement took off, he tells us proudly) thrown in.

And it’s one of the most unique, eccentric and enjoyable shows on the programme this year.

As with his 2010 show, Mohammed is in character as the bossy boots Northern lecturer Mr Swallow. This time his topic is numbers, from a bonkers breakdown of “The Twelve Days of Christmas” to some staggering mental arithmetic.

The word genius is bandied around rather too much on the Fringe but for Mohammed, who can square root a number at 10 paces and solve a Rubik’s Cube in minutes flat, it seems apt.

All of this wouldn’t work, though, without brilliant characterisation and neatly written jokes, which just keep coming in Mr Swallow’s chaotic patter.

The show may not quite keep up the bonkers momentum of its sublime first 20 minutes, but the closing trick is a little wonder, and a routine in which he eats a banana in horrified revulsion is simply unforgettable.

In all, a magical hour.

To 26 August (0131 556 6550)