When we first saw Wallace Shawn’s Aunt Dan, back in 1985, it seemed to be about the intellectual corruption of a minor, the shaping of a fascist mindset. And, yes, Dominic Cooke’s adroit revival, with Jane Horrocks as the victim of Lorraine Ashbourne’s predatory brainwashing, proves that this is still central to the play. But time and familiarity with Shawn’s later work, especially his Fever in 1990, have adjusted the emphasis. It’s you and me who are being asked to wonder if Nazi callousness isn’t surreptitiously lurking in each of us.

In The Fever, the play that launched the Court’s current Shawn season, a privileged Westerner crouches in a roach-infested hotel bedroom in a fourth-world country, convincing herself that she’s complicit with the oppression and poverty outside. For Horrocks’s sickly Lemon, sitting and sweetly smiling in front of her old doll’s house, it’s people who are the cockroaches.

We should have the honesty to admit that we need men ruthless enough to keep the world safe from the human vermin that threaten us — and we should admire the Nazis for rejecting the compassion we ourselves only pretend to feel.

In 1985 the link between Lemon’s adult beliefs and the ideas fed her in childhood by her adoptive American aunt, Ashbourne’s fiercely charismatic Dan, seemed clearer than they do now. Perhaps that was because we hadn’t long emerged from the shadow of Vietnam, for Dan is a fanatical devotee of Henry Kissinger, whom she sees as a hero braving ignominy by doing what’s ugly but necessary: bombing villages and killing innocents. In the aftermath of the Iraq War some might mount a similar defence of Rumsfeld and Cheney, so this doesn’t wholly date the play. However, it’s a more sweeping evil that now seems to be Shawn’s subject.

Myself, I’d forgotten how Aunt Dan starts by filling the 11-year-old Lemon with memories of her own louche past, recalling adulteries, orgies, even a murder committed by a woman she admires for her blithe amorality, the Sloane played by a scarily scornful, sensuous Scarlett Johnson. There’s a faint hint of homophobia in the picture, but that doesn’t date the conclusion of what’s still one of Shawn’s more arresting, disturbing plays: that child abuse can take dangerously subtle forms.

Box office: 020-7565 5000, to June 27

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