Olga's Room, Arcola, London

Olga's Room (Elyse Marks)

This emotionally gruelling piece, originally performed in 1992, was the debut play by Dea Loher who went on to become one of the most acclaimed and widely produced German dramatists of her generation.

Loher had spent a year in Brazil where she first heard about Olga Benario (1908-1942), the remarkable German-Jewish freedom fighter. Having been forced to flee to Moscow when she was twenty, Benario was chosen by the Comintern, six years later, to accompany the legendary Brazilian Communist leader, Luis Carlos Prestes, back to Brazil under assumed names.

But when his anti-fascist insurrection failed, she was captured and, now pregnant with Prestes' child, incarcerated in Rio de Janeiro prison at the mercy of a Nazi-sympathising regime which deported her to Berlin under armed guard.

Presented in a production of punishing intensity by Samuel Miller, the piece opens with Olga – played by wonderfully spiky Bethan Clark whose performance is all the more harrowing because it has such an acerbic scorn for easy sentiment – alone in a cell in Ravensbruck concentration camp, talking to herself as she tries meticulously to reconstruct her history as a way of not going mad. We then move to the Brazilian cell which she shares with Genny, a seventeen year old Romanian girl who pesters Olga for good (not necessarily true) stories to drown out her fear.

Switching between dramatised episodes and monologues, the play (eloquently translated by David Tushingham) explores the cruel dilemma of those under torture: in order not to disintegrate, your secret self has hold firm to the details of a past that your public self must expunge or deny.

At the heart of the play are Olga' s confrontations with her interrogator, Filinto Muller, an ex-guerillero now Chief of Police for the other side. Punctilious in his three-piece suit, Pete Collis is superb in the role – at once a formidable menacing presence who glories in the toying, perverted intimacies of his pseudo-God-like power and a sordid little opportunistic functionary.

But I'm not sure that I believed the ruse whereby Olga turns the tables and shows him the damage he has wreaked on his own warped psyche. And Ceridwen Smith's Ana is so heartbreaking after Muller's pornographic torture of her that the scene where he gloatingly builds up to it feels gratuitous.

It's a play, though, that will linger in the mind and leave you keen to seek out a biography of its fascinating protagonist.

To 26 January; 020 7503 1646