Charming and handsome, Alex Lippi runs an unconventional business alongside his sister, Mélanie, and her husband Marc. Their unique operation caters to worried friends and family members looking to break up relationships, particularly those where the woman has yet to realize her unhappiness. The trio meticulously devises elaborate and often costly schemes designed to deceive the women and make them believe they've found love again, only for Alex to reveal that they've rekindled his spirit, albeit too late for him to reciprocate.
The team is soon hired by a wealthy florist and gangster aiming to thwart the impending marriage of his daughter Juliette Van Der Beck to the financially secure Englishman, Jonathan Alcott, whom he disapproves of. With only ten days to unravel this union, they embark on an in-depth investigation that surprisingly reveals the depth of love between Juliette and Jonathan, complicating the mission. Unable to find any obvious flaws in the couple to exploit, Alex initially hesitates to take the job. However, he finds himself in dire financial straits due to extravagant business expenditures, leading him to reluctantly cast aside his principles in favor of completing what seems like an impossible task just five days before the wedding.
As Juliette heads to Monte Carlo for the wedding preparations, Alex takes on the role of her bodyguard, allowing him close access. With the help of his team, he bugs her hotel room and monitors her every move from an adjoining room. During his time with Juliette, Alex discovers her interests and pretends to share them, claiming to love things like Roquefort cheese, George Michael's music, and even the film Dirty Dancing. Amidst their interactions, genuine feelings begin to blossom between them, though their escalating connection is threatened by Jonathan's early arrival.
On the eve of the wedding, Juliette struggles with her emotions. In a spontaneous moment, she and Alex slip away for a night of adventure reminiscent of the beloved Dirty Dancing finale. The following morning, she openly expresses her feelings for Alex, but as he is about to follow his usual script, he recognizes that he cannot continue the charade. Instead, he urges her to proceed with her wedding plans.
As they prepare to leave the hotel, Marc inadvertently drops Juliette's case file in her presence, which reveals the surveillance photos and background details collected to sabotage her relationship. At the airport, Mélanie confronts Alex, challenging him for rejecting true love in favor of a hollow life filled with fleeting encounters. This revelation impels Alex to rush back to the wedding venue.
Meanwhile, Juliette's father informs her that although Jonathan is a good man, she would likely grow bored with him. As she approaches the altar, her father mentions that Alex had refused to accept payment for his role in the ruse. Just as she nears the end of the aisle, Juliette abruptly turns back, seeking Alex out. When they reunite, Alex finally lays bare his truths—his disdain for Roquefort, his inexperience with Dirty Dancing, and his current financial predicament that leaves him sleeping in his office. Yet, he confesses that the need to see her each day drives him.
At the "non-wedding," it's revealed that the loan shark that Alex owes actually works for Juliette's father. Meanwhile, Juliette's manipulative friend Sophie finds herself flirting with Jonathan. In the aftermath, Mélanie and Marc try to execute another scheme on their own, but Marc struggles to capture the same charisma that Alex naturally possesses, leading to a not-so-successful outcome.
