Picking up years after their summer affair in the original film, Martin (Mathieu Demy) and Constance (Romane Bohringer) have left their former spouses and formed a blended family unit together. As they embark on a joint vacation in Aveyron while Constance is heavily pregnant, their domestic life quickly disintegrates under the pressure of handling unruly children, invasive exes, and overbearing friends. As marital fatigue sets in, the boundaries of fidelity break down again as former partners (such as Martin's ex-wife Ariane and Constance's ex-husband Arnaud) re-enter their lives along with new romantic temptation.