Flo & Joan, Soho Theatre review - entertaining wit and whimsy

Musical comedy siblings Nicola and Rosie Dempsey (Flo and Joan were their grandmother and great-aunt's names) get along very well – even being mistaken for lovers by one Paris hotel who gave them a double bed – and certainly their chat between songs, where they politely interrupt each other and finish each other's sentences, is testimony to that.

So the inspiration for their new show, Before the Screaming Starts – in which they consider the possibility that their professional partnership might end in personal bitterness – was, they say, the now infamous Bros documentary After the Screaming Stops.

It's a brilliant construct that gets some airing throughout the hour, but the sisters' gentle bickering is no match for the Goss brothers' emotional fisticuffs; in reality the documentary was simply a gift for the title of their fourth show. Most of it is taken up with songs performed in a range of styles, and here the set-up is more showy, even bombastic, for a duo who previously have been known for deadpan humour.

The first number rings the changes; with Nicola, as usual, on keyboards, Rosie, previously armed with an egg shaker, takes to the drums as they go full rock 'n' roll with a song about having confidence – “I'm so confident I wear white jeans when I'm on my period.” A song about a maiden taking her strawberries to sell at a fair, meanwhile, which starts as if an old English folk song (complete with heavenly harmonising from the sisters), also shows more musical adventurousness as it segues into a hilarious hip-hop call and response, and verses pop up at intervals during the hour.

These are a departure from the pacy, syncopated delivery of much of their work, which could feel a little repetitive over an hour. Flo & Joan's esoteric subject matter, however – songs about waiting for a parcel delivery, drinking too much, Lush products and their desire to see Albus Dumbledore marry Englebert Humperdinck – is endlessly inventive

There's some gimlet-eyed observation, too, as they get great comedy in attacking anti-vaxxers (given a klezmer treatment), while they go dark in describing the kind of controlling boyfriend who looks so appealing on first meeting but then whose behaviour becomes decidedly creepy.

The final number is a breakout from previous shows too, as they have a kind of “song-off”; it's a strong ending to an entertaining performance.

• Flo & Joan are touring until 10 May

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