Given that the theatrical world is awash with productions of a Christmas Carol this tale of how the great detective, suffering a mental collapse now that Moriarty is dead and there is no criminal worth his talents to battle with, is called upon to investigate the death of Scrooge and the loss of a valuable diamond is well worth having a look at. But at times one can be a little too clever by half and one does need to know one's Dickens and Doyle to savour the full effect. But Shanahan has directed his play with considerable verve, the sets by Anna Louizos are lovely, and the six strong cast play multiple characters with the necessary aplomb. All this did not, however, stop the not so small boy and his mother seated beside me from leaving at the interval. In other words this is an evening for grown-ups. In its favour it has to be said, however, it is not an adult pantomime.

We find Holmes (Ben Caplan) in the throes of a mental breakdown. Moriarty has gone, he breaks off relations with Dr Watson (Richard James) and shouts "Bah Humbug" - or words to that effect - at all who dare cross his path. In other words Sherlock is the new Scrooge. He is visited by Dr Cratchit (Damian Lynch), actually the grown up Tiny Tim, who runs a hospital for children, with the request that he look into the mysterious death of Scrooge (Kammy Darweish oozing bonhommie) who has been found in a locked room of his house as well as that lost diamond.

You can take it from there - the ingredients of A Christmas Carol become inextricably entangled with Holmes' search for who killed Scrooge and the world of Sherlock and his friends. The denoument is suitably surprising - it is not the butler who done it - and, with the help of a little mulled wine and a mince pie or two the evening will do nicely as an alternative to pantomime - and all those productions of A Christmas Carol. A rare treat.

Sherlock Homes: Ben Caplan.

Ebenezer Scrooge: Kammy Darwelsh.

The Countess & Others: Rosie Armstrong.

Dr Watson & Others: Richard James.

Emma Wiggins & Others: Gemma Laurie.

Dr Cratchit & Others: Damian Lynch.

Director: Mark Shanahan.

Scenic Designer: AnnLouizos.

Costume Designer: Linda Cho.

Lighting Designer: Rui Rita.

Original Music & Sound Designer: John Gromada.

Fight Director: Seth Andrew Bridges.

Production Photographs: Danny Kaan.