After completing his military training, young Léo, a taciturn soldier with family problems and secret addictions, is assigned to one of the units that patrol the streets of Paris in search of possible terrorist threats as part of Operation Sentinelle.
Francis, a depressive and nostalgic thirty-something, can't get over his breakup and spends his time listening to an old French pop song that reminds him of his lost love. Forced to spend an evening Time's up with friends, Francis' obsession will test the patience of some.