Four years after their escapade in Monte Carlo, Nick (Adam Sandler) and Audrey Spitz (Jennifer Aniston) are full-time private detectives. But their business is not going too well. Accepting an invitation from their friend, Vikram "The Maharajah" Govindan (Adeel Akhtar), to attend his wedding on his private island, they hope their association with him will lend their failing detective agency some professional credibility.There, they meet Vik's French fiance Claudette Joubert (Mélanie Laurent), his flirtatious business partner Francisco Perez (Enrique Arce) (claims to have slept with 10000 women), his former fiance Countess Sekou (Jodie Turner-Smith) and her lady-in-waiting Imani (Zurin Villanueva), his reticent sister Saira (Kuhoo Verma), his ruthless bodyguard Lou (Myo Leong), and their old friend Colonel Ulenga (John Kani), who is now missing his left arm after saving Vik from an assassination attempt in Mumbai.At the wedding, Audrey notices a cloaked figure following Vik's elephant. A dead body falls from the elephant and turns out to be Vik's bodyguard, Lou. Nick suspects that it is a diversion and watches Vik's abduction by a mysterious figure. Realizing that they are once again ensnared in a conspiracy, the couple determine that at least two perpetrators must have been involved: one to create the diversion and the other to kidnap Vik. Only the board members knew about the elephant being part of the ceremony. So, they are all suspects now. Francisco tells Nick and Audrey that Claudette had to sign a brutal prenup, which the board insisted on, before marrying Vik. Saira tells them tat Claudette is just wrong for Vik. Claudette tells them that Vik knew Francisco's dark secret. Sekou says that Francisco has 85 paternity suits against him and is siphoning money from the company to pay for it.The next morning, the group is joined by a team of professional detectives led by former MI6 hostage negotiator Connor Miller (Mark Strong). Nick and Audrey try to impress Miller, but Miller considers them as a suspect since their business is failing and they need the money. The kidnapper calls and tasks Nick to deliver a ransom of $70 million to the Arc de Triomphe in Paris in exchange for Vik.Traveling to Paris, Miller takes Nick and Audrey to the exchange point with the $70 MM in cash. The kidnappers force the couple into a van at gunpoint. Inside, the couple fights them, ending with the kidnappers dead and the van crashing into Café Procope. They realize they are being framed for Vik's abduction with footage of Nick running out of the tent brandishing a knife; Miller arrives and clarifies that the footage is a deep-fake. After taking the briefcase of money and asking them to meet him at the La Madeleine, Miller is seemingly killed when his car explodes. A mysterious figure steals the briefcase, only to be robbed of it when hit by a truck. The truck driver walks away with the case.With the assistance of Inspector Laurent Delacroix (Dany Boon), the couple trace the truck to a countryside chateau where they are ambushed by Sekou and Imani, who insist they are not the kidnappers and only want the money. Sekou shoots Imani and attempts to kill the couple, but is herself shot dead by a dying Imani. Nick and Audrey escape and call de la Croix and the others, requesting that they tell the kidnappers that Vik be brought to the Le Jules Verne restaurant at the Eiffel Tower and they will hand over the money. Vik appears at the rendezvous, strapped into a bomb vest. Nick reasons that the killer would never jeopardize the ransom. As he predicts, the bomb's countdown is suspended and Miller, the mastermind of the abduction, appears; he had faked his death by hiding in a bomb-proof titanium chamber within the car moments before the explosion. He attempts to kill the group, along with Susan (Jillian Bell), a lonesome widow that was looking for her long lost lover Gary (they had promised each other to meet at the Eiffel Tower after 10 yrs on that very night), but Audrey clings to his harness and is pulled to the top floor.Nick pursues them, subdues Miller's men, and destroys the detonator. Miller throws Audrey, who is still connected to his harness, off the tower. The two men engage in hand-to-hand combat, culminating with Nick opening the briefcase and dispersing the money into the wind. Meanwhile, the group helps disengage Vik's bomb, and Susan tends to de la Croix, who was shot by Miller. Susan and de la Croix instantly fall in love after de la Croix shows her how to make circles with smoke (from his vape). Up on the top floor, Audrey reappears and helps Nick tie Miller's harness to the tower's elevator mechanism, throwing him into the rotor blades of his getaway helicopter, which explodes and crashes into the Seine.Returning to the restaurant, Audrey mistakes Saira's darkened hand for blood, but Saira insists her henna smeared during the commotion. Audrey realizes that Saira was not present when Vik's elephant was ushered into the reception ceremony, and recalls that the cloaked figure who killed Lou had a wet henna stain on their clothes. Saira is the second conspirator; she was upset that Vik's parents gave him sole control over the business, and she had previously tried to kill Vik in Mumbai. Exposed, Saira attempts to shoot Vik but he is shielded by Ulenga-who loses his right arm, then Claudette knocks her out with the briefcase.With the commotion concluded, Vik and Claudette decide to elope and give Nick and Audrey $10 million (in a dinosaur leather briefcase worth $3 MM). On a honeymoon in Greece, they are accosted at gunpoint by their supposedly European helicopter pilot who turns out to be American; he steals the millions and jumps out of the helicopter, leaving them scrambling for the controls.