Alan Ayckbourn is subtly changing as a dramatist. Where once he wrote subversive suburban comedies, his plays are now increasingly moral allegories about modern life.
And his 64th play turns out to be a logical extension of his recent trilogy, Damsels in Distress, in that it offers a timely warning about the dangers of role-playing and pretence.
There is something highly disturbing about the basic situation. Sasha, a naive country mouse living with her half-sister in a London flat, rescues an old man, Val, from a hit-and-run driver. Ironically dressed as Father Christmas, Val turns out to be an ex-villain who once ran a chain of shady clubs.
And when he showers Sasha with flowers, clothes and expensive treats, she gratefully takes everything he has to offer without realising that she is being insidiously corrupted.
Although the play is clearly a fable about the dangers of self-delusion in which Val and Sasha act out the roles of Fairy Godfather and Princess, it still has the old Ayckbourn comedy. When the arthritic Uncle Val tells Sasha's sister that he can't sit down for fear of stiffening up, her look of silent alarm speaks volumes.
And there is a priceless scene when the sister returns home to find that her flat has been given a total make-over complete with white-furred bedroom walls.
While the play is sinisterly entertaining, it also skirts certain issues. Although the old crook is besotted by Sasha's innocence, he never lays a lecherous finger on her or shows a hint of sexual jealousy, and having shown Sasha to be excessively trusting even for a Norfolk country-girl, Ayckbourn at the last endows her with a contradictory worldly wisdom.
For a play that deals with such dark matters as evil and corruption, it ends just a little too sunnily. It gains enormously, however, from its central performances. Alison Pargeter, so brilliant in the recent Ayckbourn trilogy, again shows her remarkable comic capacity. With her wide eyes and expressively large mouth, she has something of the clownlike quality of Guilietta Masina in early Fellini; yet she also conveys the hardening of the soul that overcomes the recklessly spoilt Sasha.
And the veteran actor, Rex Garner, combines paternalistic generosity and ugly menace as her gangsterish sugar daddy. Terence Booth as an ex-cop fighting to save Sasha's soul and Anna Brecon as her hysterical half-sister also turn in deft performances under Ayckbourn's direction.
But the real fascination lies in watching Ayckbourn's own transformation from social observer to impassioned moralist.
· In rep until September 13. Box office: 01723 370541.
