Trama

A suburban couple becomes embroiled in an international espionage plot when they discover that their seemingly perfect new neighbors are government spies.

Jeff Gaffney (Zach Galifianakis) works at the McDowell-Burton International (MBI), a defense contractor company based in Atlanta, as Human Resources and lives with his wife, Karen (Isla Fisher) and two children Patrick and Mikey, who are away at sleep-away camp. At his company, Jeff is the only person who has access to internet on his computer. Many employees come to Jeff to use his computer for this reason like to reorder medicines or even to video call their parents.

A new couple buys a new house, located at Jeff's Cul-De-Sac under the proprietors of Dan (Matt Walsh) & Meg Craverston (Maribeth Monroe). Meg says that the couple bought the house even without having a look first and paid all cash. Karen alerts Jeff of the new neighbors, the Joneses couple, Tim (Jon Hamm) and Natalie (Gal Gadot), and invites them over to her house to introduce themselves, surprising Jeff upon arriving home from the office.

Jeff and Karen have no sex left in their relationship, but Tim and Natalie are passionate individuals who cannot keep their hands off each other.

Karen learns that Tim is an accomplished travel writer whose hobbies include blowing glass and Natalie is a social media consultant, cooking blogger and heroine to Sri Lankan orphans. They are both impossibly good-looking, accomplished, and stylish, yet overly friendly with the Gaffneys. Tim gifts Jeff a blow glass figurine that he claims to have made himself. Karen is intrigued when Tim lets slip in passing that he knows that Jeff works at MBI, as they had just met.

Karen starts having suspicions about the Joneses when she catches Tim poking around Jeff's den during a neighborhood block party, then witnesses Natalie doing what looks like a dead drop in a cafe. Feeling unconvinced about Natalie, Karen follows her to the mall hoping to discover what she's doing, but Natalie catches Karen in the dressing room. Here, Natalie confronts her, realizing that Karen must be following her. Meanwhile, Tim invites Jeff to the Chinese restaurant to eat, but Jeff feels that getting drunk with a snake wine and being bitten by a severed snake head is not the way to make a friend and that true friendship is having an indoor skydiving experience together, a passion of his that none of his friends share. All the way through, Tim tries to have Jeff talk about his coworkers at the office.

Meanwhile Tim and Natalia break into MBI HQ & find that a suspicious email has been sent using Jeff's computer to an international arms dealer called scorpion. Back at their house, Jeff accidentally breaks the glass sculpture made by Tim that was given to them, revealing a bug among the shards. The couple now realize that they have been spied upon the whole time, and they decide to sneak to the Joneses' house to find the spying device. Inside the room, they discover that Jeff and the MBI employees are being targeted by the Joneses. However, Jeff, mistaking an item for a pen, accidentally stuns Karen with the pen gun and they narrowly escape just as the Joneses arrive at the house. Natalie is worried Tim might be getting too close to Jeff, but they reveal they are in love with each other, which is also against the rules. Natalie notices the pen gun on the floor and that it has been used, suspecting that Gaffneys might have broken into their house.

The Gaffneys arrange a meeting with MBI advisor Carl Pronger (Kevin Dunn) to explain the details about the Joneses. But before Carl can disclose further details, he is killed by a sniper who also attacks the Gaffneys. They are rescued by the Joneses, ensuing a high-speed chase and shootout. The Gaffneys learn that the Joneses are actually trying to discover whether there is treason within MBI. Back in the Cul-De-Sac, Jeff gives Tim and Natalie some relationship advice, and the two couples bond.

After they return to their houses, the Joneses trigger a bomb that blows up their house alone. The Gaffneys now learn that the Joneses are the secret agents. Later, after lying to the police about the Joneses, the Gaffneys are frantically preparing to go on the run when the Joneses reappear alive and well in their basement. They kidnapped Jeff's colleague Dan Craverston and his wife Meg, who are revealed to be trying to sell MBI's experimental microchips to an international arms dealer called "The Scorpion".

It is revealed that the international arms dealer calling himself "the Scorpion" (Patton Oswalt) is trying to take down the Joneses and acquire the microchips which could be used to weaken the U.S. missile defense system. Dan reveals that he is the one who used Jeff's computer to email the arms dealer. Jeff then accepts the offer through the Scorpion's phone call, arranging the meeting with his wife at the hotel and takes Dan's cover name, "Rascal Flatts", to deliver the microchips.

Jeff and Karen go to the hotel where the meeting takes place, while the Joneses back them up from the roof. The Scorpion turns out to be a former MBI employee named Bruce Springstine who recognizes Jeff. With their cover blown, Tim radios for backup, but the operation is aborted and the Gaffneys are declared collateral damage. The Joneses disobey orders and surrender to the Scorpion.

When the Gaffneys and the Joneses are held captive, Karen is able to pass a knife to Natalie by making out with her as a distraction, giving the Joneses an opportunity to kill Bruce's men. They escape by jumping out the window into a pool, just before the briefcase containing the chips is detonated by Natalie, and a bomb kills the Scorpion and his remaining henchmen. Proud of their new friends, the Joneses say goodbye and go back to their life of espionage. One summer later, Jeff and Karen visit the Hazim's Cafe in Marrakesh, where the Joneses used to date. They meet the Joneses, who reveal that they have left the agency. However, when four men, who might be working for another agency to track them down wearing fezzes, are seen looking at them, the Joneses engage in a gunfight with the four men, not showing the actual occurrence.