Simon works as a psychologist working for German multinational in Paris. Simon, played by Mathieu Amalric, is asked to investigate the erratic behavior of the company's CEO, Jüst (Michael Lonsdale). Simon's research leads him into obscure psychic and ultimately historical territories. We discover traces of the repressed past that haunt Jüst, a past that then begins to haunt Simon's relationship to the present -and our own.The question in Heartbeat Detector is one of language. A corporate thriller of sorts, set amidst the offices, halls and parties of the managerial class, the film is also a philosophical inquiry into how we inhabit the language we use and how language, in turn, inhabits and uses us. A collaboration with screenwriter Elisabeth Perceval, Nicolas Klotz' film is a searing comment on modern capitalism, and a reflection on how ghosts of the 20th century haunt us still. Mathieu Amalric, gives a brilliant performance in the lead role, giving Simon's character real depth and dignity.