Award-winning playwright Richard Bean, in his first home-town premiere, takes full advantage of his Hull background. As he notes himself, he can “tap into all the Hull stories people here will appreciate”, but which would make less sense to a London audience.

This can be a bit parochial, as the presence of a stranger lets the local characters point out the streets visible from the roof of Hull Prison, the A-to-Z as drama. But generally, despite the occasional uneasy clash of tone, Up on Roof successfully blends the accessible populist comedy of much of Hull Truck’s programme with something grittier and more surreal.

The grit is supplied by the 1976 riot in Hull Prison when barricades were erected, fires started and prisoners on the roof made contact with the media to publicise their grievances. In Bean’s fictional take on the events, the only thing publicised on Singe’s section of roof is the fact that he is taking no part in the riot: he is in no mood to jeopardise his imminent early release.

Unfortunately Singe has to cope with the unpredictable behaviour of his psychologically damaged side-kick Yebsley and the rather more predictable threat of Mad Hatchet Jack to whom he owes £50, plus making sense of the actions of Declan, a voluble IRA man with crazy schemes for escape, and the mysterious newcomer Christopher.

Despite the difficulty in deciding how seriously to take these characters, the invention and fantasy of the writing and the timing and conviction of the performances hold things together. Chris Connel is something of a parody of a mad axe-man, but his wild riffs on subjects from God to elephants are inspired creations. Michael Glenn Murphy, the IRA man in love with the humour of his own evil, can get away with a litany of crimes ranging from six murders to having the wrong television licence. James Weaver, as Christopher, does well in a near-impossible part, though his other-worldliness never quite convinces.

With the help of touching performances from Matt Sutton (Yebsley) and Rachel Helen (the girl in the flats next to the prison), Martin Barrass, excellent as Singe, gives the production its humanity: his near-final scene, alone on the roof in the rain, has a wordless power that legitimises the rather freakish ending that follows.

Gareth Tudor Price directs with great sensitivity to the play’s shifts of tone, accommodating the bizarre and the understated, and designer Richard Foxton’s prison roof is appropriately substantial, if somewhat battered.

- Ron Simpson