Set in an idyllic fishing village in the Basque Country, "Presunto culpable" tells the story of Jon Arístegui, a scientific researcher living Paris who, after a terrible incident, is forced to return to the village where he was born and which he abandoned ten years earlier.
There, Jon has no choice but to confront the ghosts from his past and with a mystery that was never resolved: the disappearance of his girlfriend, Anne.