Circulus, The Water Rats Theatre, London <!-- none onestar twostar fourstar fivestar -->

When did you last jig at a village dance? The scene is no rural parish hall, but a Victorian pub converted into a theatre in King's Cross. Here, Circulus belt out a humorous but seriously musical brand of psychedelic folk, as the crowd reel away enthusiastically. "This is the village dance," says front man Michael Tyack, clad in an orange smock and Oliver Cromwell black hat, before launching into a splendidly danceable instrumental.

A blend of prog revivalists and colourful troubadours heralding from some indeterminate era between medieval times and the Glorious Revolution, the band promise to deliver "an alternative reality to all this gloom" with acid-inspired songs such as "Power to the Pixies".

The barometer of the evening is three public school-types in the centre of the audience, who appear to have surrendered their bodies to the music. As the night's entertainment begins with a ditty about a burning scarecrow, they jerk their heads and shoulders as though entering into a possession. Then Tyack and his merry band launch into a ballad about dragons, and the trio start to sway their upper bodies. At the opening chords of "My Body is Made of Sunlight", a tribute to magic mushrooms, the youths raise their arms to the ceiling in a sort of Pagan act of worship before flinging themselves around wildly in the confined space.

Smoothing over problems with the sound system, Tyack distracts with poetic repartee: "Any of you, dreaming in the hollow of an oak tree, that is the theme of this song." Accompanying him on vocals, Lo Polidoro, in a flowing, red gown, is a sexy banshee with a heartbreaking wail.

"Sweet" Will Summers on the flute, recorder, "crumhorn and shawm" is the quiet star of the show, providing a funky take on traditional music making.

Whether playing to a fashionable set at the Barbican, in a muddy field in Wales or a smoky backroom in the capital, Circulus are firmly tongue in cheek; always entertaining. Their only indulgence comes at the end of the evening when their fired up fans clamour for more and they respond with a lengthy and accomplished, but ultimately dull, instrumental. Even the public school boys are subdued.