Imposter in an hour of gentle, friendly storytelling about a far-from gentle and friendly housemate Bilal Zafar found himself landed with. In less assured hands, the depiction of their strained relationship, which collapsed in spectacular style, might feel slight when told over an hour, but Zafar’s quiet control of the material draws the listener in.

His calmness in the face of the increasingly erratic behaviour of Jack, a pathological liar whose fibs get harder and harder to dismiss, is the crux of the anecdote, making it more involving than had it descended into an angry slanging match.

Jack, whose catchphrase ‘swear to God’ should have been a red flag, gets increasingly irritated that the comic isn’t rising to his ever-more provocative baits. Zafar seems unflappable, but he does have a resting sarcastic face, and voice to match, which only winds up his nemesis all the more.

The bizarre events at the London home he shares with Jack and another, more chilled-out housemate, happen during the build-up to his wedding, with calls from his wife-to-be seeking decisions on urgent but comparatively trivial aspects of the big day contrasting with the unfolding psychodrama.

Zafar offers a few side gags on topics such as bigots’ anger at seeing mixed-race couples on TV adverts,  and little peeks into his relationship. But the focus only rarely moves from the fraught situation at hand. He slowly cranks up the tension – or maybe it’s Jack’s behaviour that does that – until it comes to the first of several breaking points, and the involvement of the police and other emergency services.

It’s hard to imagine the laid-back, cool-headed person on stage getting involved in all these shenanigans. Even at its unnerving climax, Imposter is not a show bursting with energy, but Zafar makes the weird situation feel troublingly real, and tells the story with a witty detachment, able to recall every strange detail.