Are those who commit atrocities inhuman? It’s reassuring to put distance between ourselves and these ‘monsters’, but no such comfort in Nicholas Wright’s riveting, must-see play. Evil has a name, and a face, and maybe even a soul worth saving.

In 1997, South Africa’s infamous Eugene de Kock, serving a 212-year prison sentence for unthinkable crimes, was visited by psychologist Pumla Gobodo-Madikizela. This representative of Mandela’s post-apartheid Truth and Reconciliation Commission came not to blame, but to understand, even forgive – while remaining emotionally detached.

Jonathan Munby’s electrifying production begins in classic horror territory, our devil in orange jumpsuit shackled to the floor – until de Kock himself references Silence Of The Lambs with wry irony.

We’re primed for savagery, but presented with an articulate tutor, peppering his lecture with self-effacing humour. How reasonable it all is: bombing for a boss demanding results, torture giving politicians and voters the security they desire.

“The dirtiest war is the one fought in the shadows,” he reminds us, the unwitting collaborators. What abominable action is taken in our name? Is de Kock right to believe he’s just a scapegoat, a cog in the machine?

His fury’s reserved for “lies” told by the press and politically savvy wrongdoers escaping justice. He’s scornful of their euphemistic language, but uses it himself, chillingly – “pre-emptive killings”. Gobodo-Madikizela expertly draws his confession, yet with each word, de Kock reclaims the narrative.

In this charged two-hander, Noma Dumezweni conveys the struggle of conflicted empathy, while Matthew Marsh is wonderfully ambiguous, leaving us unsure whether his anguished remorse is genuine or masterful manipulation.

It’s a searingly intelligent study of a society struggling to heal, placing collective responsibility and reciprocal clemency against an endless cycle of recrimination. Yet Gobodo-Madikizela is adamant that “forgiveness is not forgetting”. Monster or not, de Kock remains caged.

Rating: Five stars

Until June 21.