A hardened CIA operative finds himself at the mercy of a precocious 9-year-old girl, having been sent undercover to surveil her family.
JJ is a former Special Forces operative now working as a CIA agent, but his lack of subtlety botches a mission and causes a bad guy to get away with some plans for a nuke. JJ and tech operator Bobbi are assigned to keep surveillance on single mom Kate and her daughter Sophie since Kate’s late husband’s brother, Victor, may try to contact them with information on the nuke plans.
Sophie finds out about JJ and blackmails him into spending time with her while she tries to make friends. She also tries setting JJ up with Kate. However, JJ and Bobbi’s superior, Kim, finds out that JJ has gotten close to them and he fires them both.
Victor finds out from a shady lawyer that Victor’s brother left the plans with his “best friend”, being the family dog Ozzie. He and his goons break into Kate and Sophie’s apartment and steal the plans from Ozzie’s collar, but JJ and Bobbi intervene. Victor steals the plans and kidnaps Sophie. JJ and Kate make it to an airfield where JJ fights Victor and saves Sophie. Victor falls to his death when he gets caught on a piece of fence latched onto his plane that gets pushed off a cliff.
JJ and Bobbi get their jobs back, but he decides to take some time off to keep spending time with Kate and Sophie.
JJ is a former US Special Forces soldier newly hired as a CIA operative. However, JJ’s lack of subtlety causes him to blow his first major mission: Busting an illegal weapons-grade plutonium trade between the Russian mafia and Hassan, a Middle East terrorist.
Despite this, his boss David Kim assigns him and tech operator Bobbi, who hero-worships JJ, to keep an eye on the in-law-family of Victor Marquez, a French illegal arms dealer who has obtained construction plans for a miniaturized nuclear bomb which he intends to sell to Hassan. Victor lost these plans to his brother David, who hid them before he was murdered by Victor himself; Kim suspects that the plans may be in the possession of David’s American wife Kate and their 9-year-old 4th grade daughter Sophie, who moved from France back to Wicker Park, Chicago, after David’s demise.
JJ and Bobbi move into the building where Kate and Sophie live, and set up their surveillance. However, Sophie soon finds one of their hidden cameras-(that was disguised as a toy ball), backtracks its signal and stumbles upon the operation post. Confronting JJ and Bobbi, she blackmails JJ into keeping her company while she tries to fit into an American kid’s life and make some new friends at her school Oaktree Charter School. Despite JJ’s social awkwardness, the two slowly begin to bond, and JJ also becomes acquainted with Kate and her gay neighbors Carlos and Todd-(who is mute). Sophie has JJ train her in the basics of the espionage trade, and brings him and her mother closer together.
However, Kim eventually finds out about JJ’s personal involvement with his targets and takes him and Bobbi off the mission. JJ reveals his assignment to Kate, who rejects him in disgust. At the same time, Victor discovers and counteracts the CIA’s surveillance and coerces his lawyer Koll into revealing where David might have hidden the plans. After faking his own death, he travels to Chicago, confronts Kate, JJ and Sophie and retrieves the plans. Carlos and Todd burst in and intervene, revealing themselves as independent arms dealers who are also after the plans. Bobbi’s clumsy attempt to help results in Victor escaping with the plans and Sophie as his hostage.
JJ and Kate pursue Victor to an airfield in Naperville, where JJ grounds Victor’s escape plane and starts a fistfight with him. In her attempt to escape, Sophie accidentally sets the plane in motion, leaving it hanging at the edge of a cliff on some wire fencing. Victor forces Sophie, who has hidden the real plans, to surrender them. Before he can shoot them, Kate clubs him onto the fence and JJ pushes the plane off the cliff, sending Victor to his death.
After being reinstated by Kim for his success, JJ has himself permanently assigned to Chicago and moves in with Kate and Sophie.
The film opens in a power plant in the Ukraine. CIA agent JJ (Dave Bautista) is a former Special Forces operative on one of his first big assignments as a spy. He tries to infiltrate a trade between the Russian mafia and Middle Eastern terrorist Hassan (Basel Daoud) for a plutonium core that can be used to level cities. JJ blows his cover when he asks Hassan who will build his weapon. Hassan knows he’s a spy, and JJ’s superiors can see all of it over the surveillance. JJ then proceeds to bust out his moves and kills many men, including Hassan, as he makes his way out of the plant.
JJ reports to the CIA headquarters in Langley where his boss, David Kim (Ken Jeong), chastises him over his failure to complete the mission, as they have no way to take down the network since JJ killed almost everyone. Another terrorist, Azar (Ali Hassan), has the other plutonium core and is still out there. Kim dismisses JJ and sends him home, where he lives by himself with his pet fish Blueberry.
In Chicago, we meet nine-year-old Sophie (Chloe Coleman), who has just moved to the area with her mom Kate (Parisa Fitz-Henley) from France and just wants to make new friends. On the bus ride to school, a few mean girls take a picture of Sophie because she accidentally left jam on her mouth.
Kim briefs the agents on Victor Marquez (Greg Bryk), a French arms dealer who was working with Hassan who has acquired Soviet schematics for a nuke. Victor’s brother David found out about his work and tried to stop him, but Victor killed him. The plan is to take Victor down before he and Azar convene to create a nuke. Kim assigns another agent, Christina (Nicola Correia-Damude), to the cooler missions and has JJ team up with tech operator Bobbi (Kristen Schaal) to keep surveillance on Kate and Sophie, as they were David’s family and want to be ready if Victor tries to make contact with Kate. Bobbi is excited because she is a big fan of JJ’s work, but he feels like this assignment is beneath him.
JJ and Bobbi are set up in a crummy apartment in the same building as Kate and Sophie. He sets up cameras in their apartment but is spotted by their dog Ozzie, who takes a liking to JJ. When Kate gets home, she has to disappoint Sophie by telling her that she cannot take her ice skating the next day like she had promised since she must take another shift at the hospital. Kate tries to ask her neighbors, a couple named Carlos (Devere Rogers) and Todd (Noah Danby) if they can, but they are busy.
Later, when JJ and Bobbi are trying to spy on Kate and Sophie, the girl comes across one of the cameras that JJ put in rather plain sight. Sophie looks up the number on the camera and tracks it back to JJ and Bobbi’s apartment. She makes her way in and records them now that she has spotted them. Although JJ tries to explain himself, Sophie threatens to expose them and post the video for all to see unless JJ does something for her. She makes him take her ice skating where he proves to not know how to do it. When Sophie tries to talk to the other girls from school, they ignore her, and the boys make fun of her. JJ trips the two boys, which gets him and Sophie kicked out, but he gets her ice cream to make up for it. When they return to the apartment, Kate is frantically looking for Sophie since she didn’t tell her where she was going to be, and she kicks JJ in the balls when she sees him with her. Sophie manages to explain things to her mom, and Kate apologizes to JJ.
Sophie later gets JJ after a morning run to help fix the pipe from the kitchen sink. He tries but accidentally sprays himself and Kate with water. Kate is also surprised to see Ozzie liking JJ since he usually doesn’t take to strangers so easily. Sophie then gets JJ and Kate to agree to let him stay for dinner, which Bobbi thinks is a bad idea since he is getting too close to them. Sophie also convinces them to let JJ be her special friend for a presentation the kids are doing with parents or other adult figures, which JJ only agrees to because Sophie is threatening to blow his cover.
JJ goes to Sophie’s school where he has to follow a bunch of people with successful careers. He tries to keep his job under wraps, but after hearing other kids make mean comments about Sophie, he tells them he is “maybe” a CIA agent and has seen and done a lot of crazy things. The kids are impressed and start talking to Sophie, and even Sophie’s teacher gives JJ her phone number. However, Sophie makes him tear it up because she secretly wants JJ and Kate to get together.
Sophie starts to ask JJ about what it takes to be a spy. He initially refuses to show her anything about it until she plays to his ego and says she might just ask Bobbi. He shows her how to pass a lie detector test, talk her way into strangers’ apartments, and how to surprise people in a fight. Bobbi feels upset that JJ didn’t show her any of this instead of Sophie.
Victor meets up with a shady lawyer, Koll (Jean-Michel Naudeau), to find out where David left the schematics. Koll says all he knew is that David said he left it with his best friend, and Victor knows what he’s talking about before stabbing Koll to death.
Sophie gets JJ to run back to the school to see her entry in an art show. He tries to complement Sophie’s work while simultaneously trashing another kid’s work…unaware that the girl and her parents just heard him, and the little girl runs away crying. JJ walks home with Kate and Sophie, and JJ admits to Kate that he’s been alone for too long that he doesn’t know how to be around people. The two continue walking and chatting with one another. He tries to show his sensitive side by helping a pigeon who looks injured by putting it on a higher surface. This only leads a hawk to swoop in and snatch the smaller bird, to JJ and Kate’s horror. When they get home, Kate invites JJ out to dinner, and he accepts. Sophie comes out after hearing everything and is excited, but when she asks JJ to dance, he shows off some pretty embarrassing moves that she begs him not to show her mom.
On the night of the date, JJ is spotted by Carlos and Todd, who give him a quick makeover so that he looks presentable for Kate. Sophie and Bobbi sit and keep an eye on JJ from the apartment. JJ tries to tell Kate the truth about himself until a song starts playing, and she wants to dance. To Sophie and Bobbi’s chagrin, JJ starts dancing. Later on, JJ helps Sophie with math homework, and Kate tells him that him being in their lives is like a breath of fresh air. Sophie also gives him a drawing she made of the two of them.
Victor and Azar meet up and go to their secret location, which Christina is observing. She reports to Kim, who instructs his agents to move in. When Victor and Azar are spotted, they run into the building, which explodes. The agents think that they are dead, but Victor is seen leaving with his own henchmen.
Following the mission’s supposed failure, Kim flies JJ and Bobbi back to Langley to tell them they are fired after they found out JJ got too close to Kate and Sophie. JJ and Bobbi part ways, and JJ is forced to come clean to Kate. She is angry, but even more so when Sophie tries to explain that she knew all about it. JJ stays in the apartment and binges on junk food in depression. Sophie visits him by pretending to walk Ozzie. He takes her back, and she tearfully figures that they will probably never see each other again, but JJ promises never to forget her.
As Bobbi is preparing to shut down to computers, she sees that Victor and his goons have entered Kate and Sophie’s apartment and is now holding them hostage. He figured that David’s best friend was Ozzie, and sure enough, the schematics are found in Ozzie’s collar. JJ tries to intervene but is taken captive as well. Carlos and Todd then arrive to step in and knock out the henchmen, but it turns out they were independent contractors who were looking for the schematics as well. Bobbi grabs some guns and tries to help out, but she drops one that goes off and fires into the apartment, allowing Victor to grab the schematics and Sophie. JJ runs after them, and Kate gets her car so they can pursue.
Victor drives to an airfield where he attempts to escape with Sophie and the schematics. JJ runs in after they make it there and gets a truck that blocks off the runway. Victor is forced to stop the plane, but the turbines cut a fuel line from the truck. JJ fights Victor as Sophie tries to get free, but she accidentally kicks the plane’s controls, making it run toward the edge of the cliff. JJ manages to free Sophie, but Victor threatens them both unless Sophie gives him the schematics. She gives him the box, but he plans to kill them anyway until Kate whacks him over the head, and he falls on the fence that has gotten caught by the plane. JJ pushes the plane over the cliff, which drags Victor down to his death. JJ recovers the schematics.
JJ and Bobbi are reinstated, though JJ tells Kim he would like to stay in Chicago with Bobbi as his partner, and she would like to stay in the van. JJ resumes his relationship with Kate and joins her and Sophie to go ice skating with her friends, where he once again shows off his dance moves and brags to Sophie’s classmates that he’s been practicing.