In an abandoned and trashed flat, sometime not too far in the future, Elliot (Ciarán Owens) and Darren (Frank C Keogh) prepare for the party from hell. Elliot is tough but clever, still in possession of historical knowledge that can inform their present, but his traumatised younger brother’s mind is full of warped versions of the past, exacerbated by his need to ingest butterflies, beautiful creatures recalibrated in playwright Philip Ridley’s world as menacing drugs.

Pretty, skinny Naz (Olly Alexander) shows up, exemplifying corrupted innocence, and we learn more about this post-apocalyptic situation. These young people have witnessed the torture and killing of those they love by marauding gangs, and know that no-one is safe anymore. To survive, they have to adopt the morals of the bad guys. The ‘party’ is in aid of making a snuff-movie for a rich, perverted City suit who has information which could keep them alive.

As the horror mounts, and the stage fills with more tragic, brutalized characters, it seems extraordinary that we can still laugh at the pitch-black humour that leavens the piece, but we do. In the tiny Old Red Lion both the story’s savagery and tenderness touch us instantaneously, and there is not a weak dramatic moment over the course of two hours.

Ridley - who is currently enjoying something of a renaissance - invents a new but recognisable world with its own coarse, vivid language. Is this how humans behave when order breaks down? Incidents from modern civil wars and genocides provide plenty of testimony to corroborate Ridley’s vision.

The Greenhouse Theatre Company have hit the ground running with this, its debut production. The cast is uniformly superb, with Olly Alexander particularly affecting as Naz, a performance which is an object lesson in inhabiting a character. Ned Bennett directs with abundant skill, and the design elements are perfectly realised.

Mercury Fur’s original reception in 2005 was part-outrage and part-adulation. Greenhouse now gives audiences the opportunity to take a position on this work while it is still fresh and undimmed by time. A remarkable play in an excellent production.

- Alison Goldie