Anonymity is a fine thing. In certain circumstances. Being a ghost writer can pay the rent, though it may not grab you the headlines. So, what about being a ghost voice, the never-officially-credited singer providing the notes the above-the-title Hollywood star couldn't reach?

That's partly what Dan Rebellato's play Showstopper is about. The starting point for the character of Carole James is Marni Nixon, who sang for Deborah Kerr (The King and I), Natalie Wood (West Side Story) and Audrey Hepburn (My Fair Lady). Even on the sleeves of the cast albums of these films, she received no credit.

Here the anonymous dubber is allowed centre stage. This is a one-woman show, though Rebecca Thornhill as Carole is constantly engaged in talking to other people - her agent, the soundtrack producer, a potential casting director or visitors to the set of The Sound of Music, in which she finally lands a part as one of the chorus of nuns.

Thornhill is blessed with a good singing voice and an engaging stage personality which overcame a potentially awkward dry in the second half. Director Pip Minnithorpe could usefully trim some of the first act, which is mainly scene-setting until we reach the audition for The Sound of Music, which has some hilarious misunderstandings and cross-purpose conversations.

The second act tips us towards something much darker. Where do the lines between appreciation and worship blur? Or between fantasy and fanaticism? Are celebrity, fame and notoriety simply facets of the same thing. And - crucially - when does the one who innocently idolises some iconic personality tip over into becoming a sinister (and potentially lethal) stalker?

- Anne Morley-Priestman (reviewed at The Regal, Stowmarket)