Like many people, Tim Firth's first stage experience came in the school Nativity play. Denied the role of Joseph, he lost his chance of holding the hand of the girl playing Mary, who was in love with his best mate. So during the holidays he wrote his first play, casting himself as a prince, Mary as the princess and his mate as the back end of a dragon.
It says much for the influence of our infant years that he's still trying to work it out of his system. Firth's script, adapted from his television play, features as many fluffed lines, missed entrances and cardboard props as you will find in the professional theatre. It also exposes what an ungodly snake pit of paediatric power-politics the staging of your average Nativity play can be.
Some argue the traditional Nativity should be replaced with more secular entertainment, and having seen this you can only agree - there's as much piety involved as a cabal of Borgias electing the next Pope. But though we learn little of the Christian message of redemption, we do discover that the Holy Infant doubles as an extremely effective cudgel.
With the possible exception of Dennis Potter's Blue Remembered Hills, the conceit of adult actors portraying children is usually embarrassing - but Nativity plays are crucibles of embarrassment anyway, so Matthew Lloyd's cheerfully chaotic production turns such awkwardness to advantage. Best of all is the manner in which Firth uses naive comedy to suggest the greater disruption of the children's lives: "Look! There's my mum!" declares Joseph. "Look! It's my social worker!" replies the Donkey. There are moments where you may wet yourself laughing. But it's your own fault for not visiting the toilet first.
· Until January 20. Box office: 0151-709 4776.
