@ Just the Tonic at The Mash House, Edinburgh, until Sun 30 Aug 2015 @22:40

It was a beleaguered audience of drowned rats that sat down in the Mash House loft, courtesy of an apocalyptic deluge tipped onto Edinburgh’s streets. Fortunately, the fortifying effects of a decent single malt went some way to raising the spirits, and Franks and Skinner did the rest with a maelstrom of a different kind.

Blazing onto the stage in matching denim and neon wigs, Lizzie Franks and Nerine Skinner begin at a million miles an hour and never let up. At first, the effect feels a little like that old lady getting screamed at by the thing oozing out of the TV in Aphex Twin’s Come to Daddy, and there was a slight worry that the duo were going to be a little much to take.

Those worries were thankfully obliterated once the rhythm was established and the crowd simply surrendered to their crazed cast of characters (including a deranged double-Cilla that they decided to leave in, and actually works as a surprisingly touching tribute to the late doyenne of easy-watching). You watch Franks and Skinner in the same way one watches a cliff-top hotel crumble into the sea; there is an uncomfortable sensation you’re witnessing the psyches of two women unravel in front of you. It’s unpredictable and completely exhilarating.

Some may find a few London-centric skits a little parochial. A series of songs on the relative personalities of the capital’s tube lines is risky north of the Watford Gap, but they are incredibly funny – and, well, anyone bonkers enough to attempt to anthropomorphise a transport system gets a thumbs up. They’ve also been thoughtful enough to throw Edinburgh’s shiny new tram line in for the local audience, which is nice of them.

The Fringe has been spoiling us this year for quality female duos, and Franks and Skinner are up there with the very best of them. Their inspired messing around was just the tonic for a miserable evening. More than worth a second drenching on the home journey.