In his recent Parlour Song, Jez Butterworth defined suburbia as a mix of the boring, the inane and the quietly desperate. Now he turns his attention to the countryside and isn’t more comforting. From the start, in which a fairy appears beneath a tacky English flag to recite Blake’s Jerusalem, you know that he’s worried about what the bureaucrats, the lookalike housing estates and, not least, the confused and alienated country people themselves are doing to our pleasant pastures and mountains green.

His Jerusalem is a bold, ebullient and often hilarious State-of-England or (almost) State-of-Olde-England play. At the stage’s centre is an American-style trailer, surrounded by discarded furniture and trees, and at the evening’s centre is its inhabitant. Mark Rylance’s Rooster Byron is an anarchic maverick, a Wiltshire lord of misrule, mythologised by his shambolic retinue of underage girls and male layabouts, among them Mackenzie Crook as a forlorn, gangling loser called Ginger. No, Rooster didn’t manage to jump Stonehenge on a motorbike, but he tells a tall story, fights a wild fight, and has stuck up two fingers at authority for aeons.

But authority is fighting back. In so far as there’s a plot in a play that’s probably too long yet never dull, it involves the impending bulldozing of Rooster’s illegal home and the banishing of those who depend on him for drugs, fun and the pounding orgy or throbbing rave that opens Ian Rickson’s energy-packed production. The angry father who brings thugs to beat and brand him can’t evict him, but the local council can and will. Mustn’t reveal too much, but can’t resist reporting that he curses a curse that magnificently draws on his Byron ancestors and the gods and giants of legend.

Clearly Byron is making a last stand for the vanishing world represented by his druidical copse and the ley line supposedly running beneath it. We’re also to compare this with the spurious St George’s Day fête in the village offstage: brewery-sponsored morris dancing, “meditation cave”, dancing dog display. Yet Butterworth, if nostalgic for the old and angered by the new, doesn’t sentimentalise his characters.

Indeed, you almost expect Jerry Springer to emerge from the woods and interview the bucolic underclass wanly on show. Rylance begins by scrambling some of his words, yet that emphasises Rooster’s quick wit. Here’s a shrewd, bold, defiant, charismatic, even mesmeric man born out of his time. Imagine King Arthur reincarnated as a troll and you have something of the quality he brings to the debased pastoral he grittily, comically and finally mournfully inhabits.

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