Pensioners Nina (Barbara Sukowa) and Madeleine (Martine Chevallier) have hidden their deep and passionate love for many decades. From the point of view of those surrounding them, including Madeleine's meddling daughter (Lea Drucker), they are simply two neighbors sharing a hallway during their sunset years. In reality, this landing is a bridge between two worlds: one belonging to a widowed, doting grandmother, the other to a free-spirited, fiercely independent woman who longs to spend her life with the person she loves. Clandestinely, Nina and Madeleine share a tender life, moving freely between their apartments until, one day, an unexpected event closes the portal. In this new reality, their secret cannot remain hidden if they are to stay together -- and their unconditional love is put to the test.