It's one of the stranger stories from Brighton's chequered past: a spate of poisonings in 1871, tracked in the end to strychnine-laced chocolates. And this gothic comedy of a puppet show is fittingly dainty and sweet; performed with miniature glove puppets on an adorable fold-out set, it's full of knowing humour, yet still does justice to the grotesque historical tale.

This isn't a whodunit – in fact, it's a running joke that the perpetrator's identity is so transparently clear. The story lies in why she's done it, and in her increasingly unhinged attempts to conceal past crimes by committing more and more of them. A scene where the puppet villain reasons through the logic of mass murder is a dark comic highlight, and her premature imagining of a victim's fate is a masterpiece of twisted glee.

The puppets are all operated by performer Daisy Jordan – who also, as narrator, is very much a character in the show. More than any puppeteer I've seen of late, Jordan succeeds in giving her creations an identity separate to her own. Sometimes, she comforts them; sometimes, she scolds them; sometimes (and these are the best times) they scold her back. One of them, hilariously, knows that he's in a show, teasing the audience with false leads and occasional cutting asides.

But it's the jokey little details I enjoyed the most – like the way the handsome love interest repeatedly lifts his tiny puppet hand to flick his tiny puppet hair. Later, when a puffed-up but bumbling policeman arrives, he unleashes a second wave of comedy: now the joke's around his hapless investigation, and his inability to spot a truth that's so plain for him to see.

But of course, this isn't an entirely carefree tale. The first scene features a candy baby packaged in a tiny cardboard coffin, and the reason for that – a tragic reason – becomes clear towards the end. When the moment comes, it's sensitively handled: a pause for reflection on the true human story that underpins this apparent melodrama.

The Sorrowful Tale of Sleeping Sidney is, for me, the kind of charming small-scale show which defines the Fringe. It's funny, self-aware, skilful – and beautifully realised in its seaside milieu. So. go and see it; because if you miss it, the sorrowful one will be you.