Some important features of Patricia Highsmith's character are reflected in what occurs in her hugely successful first novel, Strangers on a Train or, at any rate, in Craig Warner's gripping play "based on" it. They include addiction to alcohol, which was to become a life-long curse for her, an appetite for same-sex relationships, and, on one occasion, the embracing of the dangerous fantasies of a stalker after she tracked a woman she served in a department store to her suburban home, and watched her secretly. "Murder is a kind of making love, a kind of possessing," she mused about the episode in her diary.

That was in 1948, two years before her sensational fictional debut. The psychological understanding shown in the novel also seen later in her superb 'Mr Ripley' series struck an immediate chord with filmmaker Alfred Hitchcock who fashioned from it, with the help of screenwriter Raymond Chandler (now there's a dream team!), one of his best-regarded movies. This took certain liberties with the story, including turning one of the central characters from an architect into a tennis player, deemed a rather 'sexier' occupation, one supposes.

Guy Haines (Will Thorp) is dreaming up great new buildings once more in the stage version though his creativity is being stymied by the infidelities of his wife. He rashly confides this fact to the garrulous stranger who seeks out his company (sexual attraction?) during a train journey. Charles Bruno (Alex Ferns) has a problem of his own in the form of a hated father. He has an idea: why doesn't each dispose of the other's trouble in what would appear to investigators to be two motiveless murders?

The increasingly nutty and dipsomaniac Charlie goes on to fulfil his side of a bargain that has never actually been made. He then begins a tireless campaign of blackmail and intimidation to wear down the good-sort Guy to do his bit.

Under director Robin Herford, who brought Susan Hill's Woman in Black to the stage, this provides taut, gripping theatre. There are admirable performances from the whole cast, which also includes Leah Bracknell as Guy's easy-going (and mighty puzzled) new wife, Anita Harris as Charlie's doting mother, and Colin Baker as a deceptively dumb-looking private dick.

This excellent production can be seen until tomorrow at the Everyman, Cheltenham (01242 572573). The tour continues at the Wycombe Swan (01494 512000) from June 12-17 and Milton Keynes Theatre (0870 060 6652) from July 31 to August 5.