Adapted from the awarded-winning novel by French novelist Philippe Grimbert and produced by Yves Marmion for UGC, the film - Miller's thirteenth feature - features de France, Patrick Bruel, Ludivine Sagnier, Mathieu Amalric, Julie Depardieu and Yves Jacques.
The story follows the life of a Jewish family after WWII, as a young son invents a brother and imagines a past of which his parents never speak. On his fifteenth birthday, a family friend reveals a shattering truth that will enable him to develop his own personality at last.
UGC is selling the film and will distribute in France. Un Secret will be released in Canada by TVA.