Guillaume Canet stars in Guillaume Nicloux's suspenseful post-noir thriller La Clef (The Key) as Eric Vincent, a thirtysomething whose wife, Audrey (Marie Gillain) longs for a baby. A troubled situation involving Eric's own dad, however (including years of estrangement) makes him extremely reluctant to father a child himself. One day, a call arrives, and a mysterious stranger on the other end both announces the death of Eric's father and invites Eric to reclaim the gentleman's ashes. This sets into motion a chain of events that will entangle the young man in a series of endless complications - complications involving drug dealers, professional thieves, long-buried family skeletons and a host of other ills. As the story unfolds, Nicloux criss-crosses two narratives: a crime-themed account set in the present, and a chain-of-events set in the past that details how Eric's life became enmeshed in a web of deadening violence.
~ Nathan Southern, All Movie Guide