Listen, you haven’t really done Fringe 2024 until you’ve seen the one-man musical cabaret about sperm donation, have you? This vibrant little gem from musician, songwriter and performer Darby James has a suitably attention-grabbing, bonkers hook to it. But it’s the absolute real deal in its sincerity, warmth, and wonderful storytelling. Four years ago, during the covid pandemic, a Facebook ad popped up on James’ computer, seeking sperm donors. Intrigued, and moved enough by the idea that he could help others to conceive, he decided to take the plunge (as it were).

This show charts not only the fascinating practicalities of sperm donation, with all its bureaucracy and micro-decision-making, but also asks bigger questions about conception ethics and individual responsibility. James is a fantastic yarn-spinner, candid, self-deprecating and eloquent. He has harnessed his material well and blends heartfelt examinations of all the tangled issues he was forced to confront with a gripping structure that respects the dynamics and craft of memoir.

But the jewel in this crown is James’ songwriting. His wordplay and Broadway energy carry echoes of Sondheim, while he tackles a broad range of styles from shanties to electro-pop to soaring belters. The decision to limit his stage space to a small, single circle, while symbolic, feels restrictive at times, and James as a performer occasionally seems like he is holding back (perhaps because of the staging). But this is a rare piece of musical theatre: unexpected, thought-provoking and bursting with heart. 

Little Squirt, Summerhall, until 26 August, 7.40pm; main picture: Lucinda Goodwin.