As he makes clear in the introduction to the printed text, Neil LaBute’s latest London premiere is both an excavation of his own childhood and a deliberate homage to both Sam Shepard and Ingmar Bergman. Two brothers return to their childhood and the dark secrets of a violent father and an abusive family friend.

Sounds grim? Yet more dramatic chest-beating as a form of self-therapy? Haven’t we just about had enough family reunions this week from T S Eliot and Steppenwolf? Yes to all three questions, but LaBute loads his dice in a fascinating way and Michael Attenborough’s involving production has two remarkable, unstrained performances from David Morrissey and Steven Mackintosh.

The scene is an adaptable greensward, first the grounds of an institution, bordered with firs and rushes, where Mackintosh’s Drew, a married lawyer with a drink and promiscuity problem, is visited by his older brother, Morrissey’s Terry, a mixed up security guard (though we don’t know that yet). It’s Drew’s last chance to come clean. Terry helps him out.

Next, we’re on the thirteenth green at a novelty putting course, where Terry has tracked down the teenage daughter, Jennifer, of the family friend who abused his brother. They strike a bet, play the hole, then play around. American actress Kira Sternbach is a flirtatious Lolita, cleaning out the putting holes in her red hot pants and flapping blouse. A scene of curious friendship and holiday humour darkens to one pregnant with sexual options and revenge opportunities. Anything could happen.

Finally, the grass becomes that of Drew’s back garden where a welcome home party is in full swing and Terry returns with news of Jennifer’s father. This time, he’s the vulnerable one, and that conversation we’ve been avoiding all our lives with our nearest and dearest comes tumbling out. The switch of strength and dependency is brilliantly handled and you suddenly realise that no one is safe from the fears at the bottom of the garden in the tree house. Was there any such thing as an idyllic childhood?

And if so, could that idyll be an unusual one, where abuse is friendship and perversion a pleasure? LaBute makes it hard for us to see things straight, as usual, and Morrissey finds an unexpected softness in his armoury, while Mackintosh seems to have taken childhood with him into the grown-up jungle. An anecdotal trifle assumes a bleak and tragic dimension.

- Michael Coveney