Lionel operates a commuter train in Paris, where he lives with his daughter, Josephine. Their life together is simple and blissful, as they are content with each other’s company. While Lionel, a widower, is reaching the age of retirement, Josephine is making her way into the adult world as an university student. The caring father begins to realise that his child is no longer a child, and that the dynamic between them is bound to change when Josephine’s bond with their neighbour Noé deepens.