Juan, Luis Tosar, is a middle-aged Spanish intelligence operative who leads a tight, capable team—a hacker and a versatile female operative. He tracks a wealthy couple involved with a neo-Nazi leader and a weapons trafficker, while also keeping tabs on a newly elected congressman, Ángel González, Denís Gómez.
To gain access to the mansion, the team stages the kidnapping of the couple's live-in Filipino maid, Wendy, Alexandra Masangkay, making it look like Juan is another kidnapping victim. The plan has them dumping the pair from the vehicle at a stop, creating the opening for Juan to meet Wendy. He uses the budding romance to gain entry to the house and install hidden cameras.
As the surveillance continues, the team uncovers evidence that the couple plans to bring a black-market cobalt-60 into Spain, potentially part of a dirty bomb plot. Despite using Wendy as part of the operation, Juan grows emotionally attached to her. Wendy shares her dream of saving enough from her work to return to the Philippines and open a bed-and-breakfast with her sisters.
Back at the political front, Galán, a career-driven officer with political connections, assigns Juan to look into the life of the newly elected congressman Ángel González for illegal or unethical conduct. When the initial hacking and video surveillance yield no clear misconduct, Galán pushes Juan to lure the politician into a compromising situation. Juan pressures Marta, a teenage girl he knows from a previous case, to participate in a honey trap, sending flirtatious messages to Ángel on a dating site. Marta Georgina Amorós meets Ángel for drinks at a nightclub, then returns with him to a hotel room where Juan has installed a video camera.
After they have sex, Marta goes into the bathroom and smashes her nose into the sink, then flees into the hall. Juan confronts Ángel, informing him that he has just slept with a minor. Marta, sickened by her role in the setup, smashes Juan's surveillance-laptop and flees, though the recording remains intact.
Meanwhile, Wendy discovers Juan's deception. After Juan and his team track the cobalt-60 shipment and arrest the smugglers, police arrest the weapons-trafficking couple, but Wendy is away from the house. He asks her to stay at his apartment until she can resettle. He then provides travel documents and a ticket to the Philippines, and gives a hard disk of his surveillance operations to a reporter to reveal the intelligence service’s unethical and illegal practices. In the end, Juan abandons his old life to join Wendy in the Philippines.
