The 23-year-old Demi Lardner is performing at the Fringe as Gavin, a 46-year-old man, seemingly dressed in school gym kit, and stuck in his basement with only telemarketer Sandra for company on the phone. If it sounds bizarre, it is, but wonderfully so. The calls aren't pre-recorded, which lends a sense of spontaneity to the dialogue as Sandra asks Gavin a series of odd questions. There's innuendo, diary reading, dream sequences, terrible erotic fiction and physical comedy all packed into this madcap hour that doesn't pretend to be anything loftier than pure entertainment.

Australian Lardner is the sort of comedian who divides a room: most are throwing their heads back and howling with laughter while others look on thoroughly bemused. She's entirely uncompromising in her weirdness, breaking the fourth wall to smirk at her own ridiculousness and throwing out asides like 'I went to uni' that ensures the surreal nature of the hour feels inclusive rather than alienating. Be warned, though, she's going to ruin Dyson hand dryers for you.

Underbelly Cowgate, until 27 Aug, 9.20pm, £10–£11 (£9–£10).