Foot / Mouth, Soho Theatre, London

The National Youth Theatre's summer residency in Soho is ambitiously split between a "six pack" of three double-bills of large cast plays with body parts: the dystopian, inter-linked Foot and Mouth by John Nicholson and Steven Canny play in repertoire with Tits/Teeth (boob jobs and disco mania) and Eye/Balls (sex trade and stag night).

It's not too far a cry from the old NYT mob dramas about football fans and suffragettes which rotated with the odd Coriolanus or Henry V, but it does look as though the company of schoolchildren and young people labelled "NEETs" (not in employment, education or training) has moved over- drastically with the times.

In Foot, the year is 2025 and an odd foot is found on a beach on the Lizard peninsula. Sarah is texting Tim, a blind date, and by the time they meet there are odd feet everywhere. Cornwall has seceded from Great Britain as an independent Celtic state, following the Conservative Party landslide of 2010 and complete withdrawal from Europe. But there is a spy mission in Cornwall, probably unrelated to the foot fetish, which is fuelling paranoia in the media (the rolling news station "Skytanta" is populated by heavy-breathing bimbos) and in the police and coastal guard services, who members are portrayed as gormless apparatchiks as might have been imagined by WS Gilbert and the Keystone Cops.

In Mouth, the Cornish party is shipwrecked on the south coast and infiltrates England, where the language has evolved into an Orwellian gobbledegook littered with the names of tyrants and – an odd NYT in-joke, this – Diana Quick. All forms of communication using digital technology have been outlawed. Society has been de-sensitised by its own scientific endgame.

But the community keeps reverting to odd behavior and old jokes. Someone who says he was raised by badgers claims he fell in with the wrong sett. Sarah (plaintively played by Jo Rayner) has been separated from her own family while Tim (fresh-faced, eager James Camp) has confessed to being a spy for love and his country. The cast of 20, directed by Andy Burden, do their best to keep up with the nutty surrealism of the writing, but the tone is all wrong and the evening starts sinking irrevocably into a quagmire of numbingly unfunny exchanges and feeble ensemble set pieces.

There's not much bite to the political satire because the system, and the projected fantasy situation, is not examined closely enough. The use of video screens is haphazard, too, although Chloe Larnford's designs are otherwise neat and clever, with a mobile cupboard containing the comedy officials and, at one point, a teeming populace.

Each play, curiously, evaporates in a cloud of confusion, with no stirring narrative conclusion or showcase for what always used to be the defining factor in any good NYT show: a rousing display of corporate solidarity.

To 10 September (020 7478 0100; www.sohotheatre.com)