Some 50 years ago, two American script-writers – Richard Levinson and William Link – created a Los Angeles detective called Columba. It was for a television mystery series and the play was called Enough Rope (as in “...to hang yourself”). Columba’s creators weren’t going to let a good idea fade after one outing, so they re-cast it as a stage play – Prescription: Murder.

That’s the show which is currently on tour. Our dishevelled hero is played by John Guerrasio, who incorporates many of the mannerisms familiar from Peter Falk in the long-running television series but still manages to make the part his own in Michel Lunney’s production. The play suffers from the old division into three distinct acts coupled to the modern trend towards having only one interval and from scene changes which drop the tension along with the curtain.

If Columba is the hero, the villain is Brian Capron as Dr Flemming, the steely psychiatrist who resorts to murder in order to rid himself of his wife. We know he committed the crime; Capron’s strangulation of Claire (Alexandra Boyd) is protracted to the audience-giggles stage. Elizabeth Lowe is Flemming’s new love interest, a long-legged actress much smarter in her dress sense than in following the script improvised by her lover.

It’s a moral play, in so far as professional integrity winning out over strong-pulling, the misguided eventually doing the right thing and a murderer getting his just desserts is concerned. It’s well cast, equally well acted and the sets look good. But the scene changes give the audience too much time to pick holes in the two-dimensional characters and stock situations. A murder mystery doesn’t have to be realistic. But it does need to be gripping. Columba apart, we don’t really care what happens to any of these people.