Making their Edinburgh debut, the poster for the Moscow Boys implies plenty of music, played with high energy. But just how much energy is truly jaw dropping. Has a string quartet ever moved so much whilst rarely dropping a note? No wonder you can see the sweat flying off only 10 minutes in.

A mish-mash of styles and genres – part concert, part cabaret and part sketch show – the show is essentially the story of the world’s naughtiest string quartet as, sneaking behind the back of their strict conductor, the boys let loose and play exactly what they want. Particular highlights include a delightfully sexual rendition of From Russia With Love, (with plentiful hip thrusting) and a cheesy tribute to Hero, that sickeningly ever-present 00’s love song.

Frequently, the players plumb their Russian heritage, flirting and charming their way through Tchaikovsky’s Flower Waltz with a series of fabulous hats. Most wonderfully, they perform Swan Lake’s The Dance of the Cygnets with very similar (and terrifyingly energetic) choreography to the original ballet. The movement is almost constant and infectiously joyous. The boys tap, salsa and high kick their way across stage, sometimes stopping to lift each other on their backs when it looks like things are getting too easy.

Much of the music – and there is so much – sparks something deeply comforting, in terms of recognition. ‘I know this…’, you mumble, as your feet compulsively tap away. It’s like a beautiful dressing up box of snatched childhood melodies – adverts, tv themes, half-heard songs on the radio.

It’s a shame therefore that the talent is sometimes let down by the sound mixing, with the volume occasionally so loud as to be painful. The backing sound effects can also be overly dominant. Often they work well with the narrative of a sketch/segment but bury the virtuoso playing. Shakira’s Obsession come across very nicely as a screeching string piece, until it is drowned out by slightly inexplicable and shrill phone ringtones. But even with sore ears, it’s hard not to come out grinning from one to the other. In a grey world, the Moscow Boys are an exhausting rainbow.