MORAL compasses are spinning out of control in Rob Johnston’s black comedy Under My Skin, aired this week as part of Liverpool’s Write Now festival of one-act plays.

Flatmates Will (Adam Davies) and Jimmy (Andy Sykes) are extremely likeable, despite being in dire need of a conscience transplant, and are realistically drawn, even though their actions are wildly out of the ordinary.

Davies charms the audience with his charismatic opening monologue about robbing politicians and the pointlessness of guilt – before hinting that he has just murdered and carved up his best mate’s ex-girlfriend.

It’s a twist that calls for a laugh, rather than an intake of breath, and the scene is set for a show that knows how to draw out the humour in the darkest of human impulses.

Before long, Jimmy has been manipulated into Will’s way of thinking, and an unfortunate encounter with a stranger in a pub (Peter Carruthers) ends in tragedy.

Johnston’s dialogue is excellent – he, to borrow the name of the play, really gets under the skin of the characters.

Even the incidental roles are intriguing – the police officer who arrives just in time to send Jimmy into a spiral of panic deserves a play all of his own. Even Rose (Ruth Piggott), who appears as a very down-to-earth ghost, is resigned to the fact that most people are naturally bad, and is visibly bored by her ex-boyfriend’s growing guilt.

Some elements of the plot get a bit over- complicated, but for the most part Johnson plays to the strengths of the one-act format.

It’s just the right length and, at the point when you’re wondering how the whole thing is going to end, it finishes with a laugh.

UNDER My Skin is playing at the Actors’ Studio, Seel Street, Liverpool, 7pm tonight, 8.30pm on Wednesday and 2.30pm on Saturday.