Theresa has an ectoplasm problem. She has been sharing her flat with a 600-year-old tormented spirit which manifests itself as a puff of putrid-smelling smoke. He is a very particular spook, however, choosing only to materialise before Theresa's dumbfounded pal Donna, staying in the flat to escape the creepily persistent overtures of an unwanted boyfriend. Now she has two stalkers, one from either side of the grave.
Bryony Lavery's play is, to say the least, unconventional: mixing elements of Victorian shocker Gaslight with the linguistic register of a raucous girls' night out. And it is at least intermittently funny: "Why does stuff always happen to me?" wails Sally Carman's hapless Donna. "I'm a good person. I give to earthquake appeals! I buy the Big Issue!"
Lavery mixes styles and registers in a manner that is frequently awkward and occasionally downright bizarre. In fact it becomes difficult to nominate the most embarrassing moment: is it Theresa's use of the word "twat" as a term of endearment? Or the point when Donna pretends to soil herself? Or when both women sniff curiously at a penis-shaped candle?
Gwenda Hughes's production does its best to keep pace with the play's sudden changes of mood, but there are points where its paranormal ambitions become impossible to pull off. The published stage directions call for a face-pack to "burst into flame with centuries of frustration": what one actually sees is an actor being harassed by some dry ice and a lighting effect. None of this would be a problem if the play were consistent enough to give the situation some credibility. But as Theresa herself exclaims: "I'm so not believing this."
· Until March 4. Box office: 01782 717962.