Director Emily Louizou has found the perfect space for Tejas Verdes, Fermín Cabal’s 2004 collection of seven haunting monologues surrounding the disappearance, torture, and death of a young woman in Pinochet’s 1970s Chile.

Louizou’s company, Collide Theatre, has converted the upper floor of Ugly Duck, a quirky venue near Tower Bridge, into a discomfiting, multi-room landscape of suffering, eerily lit by Guido Garcia Lueches and strikingly designed by Adelaide Green. Audiences have free rein to walk throughout the space as five women appear in turn, each delivering directly to individual members of the audience. A monologue (or two) zoom out from the political prisoner herself, Colorina (Ava Pickett), to the friend with whom she shared a cell (the superb Evelyn Lockley), and onwards to the gravedigger (Susan Hoffman) responsible for the unmarked tombs of the secret police’s victims.

Louizou’s promenade staging works to great effect in conveying the sense of a disturbing visit to a shadowy museum of prison cells, although it perhaps allows a little too much audience freedom in a play that tries so viscerally to represent oppression and confinement. During the two monologues that take place in the smaller, brighter rooms, the relationships between speakers and audience become somewhat murkier – are they addressing us? Are we the judge, the press, omniscient observers?

Cabal’s play, here in a translation by Robert Shaw, opens with a verbal depiction of graphic violence, and the gritty intensity never lets up. Lockley’s gripping performance towers above the rest of the production, in part because Cabal gifts her character with far more nuance than he does anyone else, as well as a searing twist in her second monologue. And while the play commits to an occasionally stifling humourlessness, Lockley manages to find wry ironies in her twisted experiences, as if conjuring up the distant memories of laughter; she’s never funny, understandably, but she’s fully human.

As, respectively, the hardened doctor who once examined Colorina, and the cold lawyer representing Pinochet decades later, Hayley Hirsch and Frances Keaton make the most they can out of parts with disappointing lack of depth. (Only Lockley’s role calls to mind the wrenching psychological complexity of a superior play inspired by Pinochet’s regime, Ariel Dorfman’s Death and the Maiden.)

It seems in poor taste to compare the atrocities of the Pinochet dictatorship with contemporary politics, but it’s hard to resist the temptation after hearing the doctor deny her role in Colorina’s torture, suggesting that the government has the power to decide what is truth and what is fiction. It’s a comparison that Louizou’s programme note invites as well. And while Cabal doesn’t provide any easy answers, the stories told still need to be heard, and the questions posed – about sacrifice, betrayal, and bravery in the face of tyranny – still need to be asked.

Tejas Verdes played at Ugly Duck from 1-2 April.