For the first 30 minutes of this film about a failed relationship, director François Ozon seems well on his way to a magnum opus. In two fiercely lucid scenes (of the title's five), he creates a work of indelible cinema, attuned so sharply to the cadences of human relationship as to feel shockingly, bracingly alive. And then, piece by piece, Ozon (director of Under the Sand and Swimming Pool) undermines his own work. 5x2 travels backward through milestones in a relationship between Marion (Valeria Bruni-Tedeschi) and Gilles (Stephane Freiss). We open with their divorce and proceed through an important evening with Gilles' brother (Antoine Chappey), the birth of the couple's child, their wedding night, and so on. The problem is that Gilles is an aggressive, childish asshole. The film could have examined where relationships falter, but instead it merely shows what happens when a good woman marries the wrong man. For anyone who believes in the gorgeously messy truth of French social drama, it's a grave disappointment.