Greg, the founder of the successful agency Alibi.com which specializes in crafting elaborate cover stories for unfaithful partners or tricky social situations, is finally ready to settle down. Having successfully repaired his relationship with Flo after the chaotic events of the first film, Greg proposes to her. Flo happily accepts, but the road to the altar is paved with impending disaster when the topic of wedding guests arises. Flo insists that Greg invite his parents.This simple request sets off a frantic crisis. Greg is deeply ashamed of his
dysfunctional family background. His father, Gérard, is a former con man and washed-up actor given to theatrical lies, while his mother, Marlène, is a former erotic film actress whose past is wildly incompatible with Flo’s upscale, conservative parents, Catherine and Daniel. Desperate to present a respectable image, Greg decides to re-engage his agency's services. He hires actors to play his refined, upper-class parents, hoping to fool Flo and her family during the engagement festivities.Naturally, the deception immediately begins to unravel. Gérard and Marlène discover Greg's plan to replace them and feel deeply hurt and rejected. Refusing to be sidelined, they crash the engagement dinner disguised as domestic staff and eccentric guests, determined to sabotage the fake parents. At the same time, Greg’s
business partner Medhi and associate Augustin get bogged down in their own absurd alibis, trying to cover for clients while managing the escalating chaos at Greg’s luxury venue.As the weekend progresses, a cascade of misunderstandings, accidental reveals, and escalating fibs turns the celebration into an absolute circus. Flo's father Daniel becomes suspicious, while Greg's real parents lean harder into their outrageous antics, exposing the sheer hypocrisy of Greg’s manufactured perfection. Secrets spill out over dinner, leading to explosive confrontations and public humiliations. Flo is devastated to discover the elaborate web of lies Greg has spun once again, feeling that he still does not trust her with his true self.Left alone and facing the cancellation of the wedding, Greg finally realizes that his obsession with image has ruined his life. He decides to come completely clean, publicly embracing his eccentric parents and their colorful past without any filters or fake alibis. Moved by his genuine remorse and vulnerability, Flo forgives him. The film culminates in a chaotic yet joyous wedding where Greg’s real family and friends celebrate together, proving that love and acceptance triumph over deceit and social pretense.