And Then There Were None began life as an Agatha Christie thriller with an entirely different title. Delicately crafted, it was one of the most popular books she ever wrote and one of the most technically clever. A group of guests is invited to spend time in a fine house on a remote island - one by one they die. Murder 1930s-style is rampant.

After the book was published, Christie turned it into a play, and the theatre company named after her exists to tour such adaptations around the country. Dramatically, it is a tough call: one set, ten main players . . . decreasing in number every now and then. Any stage time not taken up by working out who the murderer might be has to be used up by characters introducing themselves and posing decorously on the excellent set. Mysterious exits and entrances from surprising places, explosive gunshots, suddenly dead people who have been in the audience's view for some time: this is all grist to the mill for a Christie theatre audience.

And they were there in coachloads at the Playhouse on opening night. No one should approach this play with any degree of seriousness: indeed there are moments when Agatha Christie herself clearly wrote lines for laughter.

Trying to work out whodunit' is the entire point of the game and thus makes it quite impossible for any sane reviewer to do anything other than box and cox a bit with their readers and talk about the actors.

All of whom were spot on. The company played the mystery admirably straight, with the iconic Gerald Harper as Judge/Detective steering the company of suspects in a relaxed but firm Holmesian way. Mark Wynter impressed as Dr Armstrong, Peter Byrne (General McKenzie) had fun in his role and - good for him - was still entirely recognisable from his Dixon of Dock Green years. Chloe Newsome (pictured) was vivacious in all the right ways.

This is solid, absolutely middle-of-the-road stage entertainment, with only a very few ennuis, and all the better for that. I desperately want to tell you whodunit, and I know I have.

And Then There Were None continues until Saturday evening. Box office: 01865 305305 (oxfordplayhouse.com).