Noomi Rapace plays Maja, a transplanted Romanian who, in the years since World War II has built a new life with her American husband, Lewis (Chris Messina), keeping her darkest memories to herself. Those memories threaten to upend that life when, on the serene streets of her small town, she recognises a former German soldier and sets in motion a series of drastic events to confront the trauma she believes he inflicted on her.

Enjoying a lackadaisical picnic with her young son, Patrick (Jackson Vincent), Maja goes into high alert when a tall blonde man walks by, and in short order she has followed him home to get a better look.

The material takes bold chances, beginning with Maja's lying in wait for the man when he gets off his shift at the refinery and kidnapping him in broad daylight. She drives him to a remote location where she's already dug a grave, but, unable to bring herself to do the deed, she takes him home.

Tied to a chair in the basement, the man insists that he's a Swiss citizen named Thomas, not the Karl of Maja's most painful memories. As she pursues her programme of interrogation and torture, she also must fill in Lewis on her wartime experiences, far more harrowing than what she'd previously let on, beginning with her identity as a member of the persecuted Roma, known disparagingly as gypsies.

A devoted husband, Lewis becomes Maja's reluctant – but not all that reluctant – co-conspirator. Worried calls to a psychiatrist notwithstanding, he's on board, if only to protect his spouse and their comfortable family life. In what may be the movie's low point, Lewis comes home from work to find that Maja has been busy pursuing truth in the basement.

As neighbours grow suspicious and Patrick flinches from his wild-eyed – and blood-spattered – mother, Lewis tries to quell his skepticism and sort out whether Thomas is indeed the rapist and murderer Maja claims he is. The dark doings downstairs increasingly become a test of the couple's bond.

The story at its weakest it's distractingly off-key; at its strongest it's steeped in an almost ghostly atmosphere of trauma, peering into what we choose to look away from or bury in silence – and how long that can endure.