Three out of Five stars
Running time: 135 mins

Slow-moving, superbly acted French thriller that gradually exerts a tight grip, providing you can handle the lengthy running time.

What's it all about?
Based on the 2000 novel by Francois Emmanuel, Heartbeat Detector (or La Question Humaine, original title fans) stars ubiquitous French actor Mathieu Amalric as corporate psychologist Simon Kessel, who works for the Parisian branch of a German-owned petro-chemical multinational called SC Farb. Assigned to investigate the erratic behaviour of CEO Mathias Just (Michael Lonsdale), Simon begins to research the Farb Quartet, a work-based string quartet for which Just once played.

As his investigation progresses, Kessel uncovers a dark secret involving the company's collaboration with the Nazis during the war, and his interviews with Just and his colleagues take on a cat-and-mouse quality. Meanwhile, he has hands full both with his everyday work routine and the pressures of juggling two women: on-off girlfriend Louisa (Laetitia Spigarelli) and office hottie Isabelle (Delphine Chuillot).

The Good
Munich co-stars Mathieu Amalric and Michael Lonsdale generate an intriguing chemistry during the interview scenes and there's strong support from both Laetitia Spigarelli and Delphine Chuillot. In addition, Valerie Dreville makes an impression as Just's loyal secretary and Jean-Pierre Kalfon is superb as Simon's equally shady boss.

The script is admittedly quite dense, but there's plenty to think about and it throws up some interesting themes. In addition, the seemingly innocuous English title of the film takes on a chilling significance when its true meaning is revealed.

The Bad
That said, the film is a little too long and drags considerably in the middle section. This isn't helped by the odd musical sequences, particularly a scene of Kessel and Louisa listening to a singing performance in a restaurant that goes on for about five minutes. There's also a rave sequence that seems oddly out of place.

Worth seeing?
In short, Heartbeat Detector is an intriguing thriller with strong performances and a dense, complex script, but it may be a little too arthouse for some tastes and the lengthy running time takes a definite toll.