In The Pacifier, Shane Wolfe (played by Vin Diesel) is a highly skilled and tough Navy SEAL who fails a mission to retrieve a top-secret device known as the GHOST. As punishment, he is given the job of protecting the family of the device's inventor, Dr. Howard Plummer, who was killed during the failed mission. Shane is assigned to stay at the Plummers' suburban home and watch over their five children while their mother, a scientist herself, is away on a mission.
The Plummers include oldest daughter Zoe, rebellious teen Seth, middle child Lulu, young Peter, and baby Tyler. Shane finds it difficult to connect with the kids, who view him as an intrusive stranger. He is particularly challenged by their daily routines and the various demands they place upon him.
As Shane tries to navigate his role as a caregiver, he discovers that Dr. Plummer hid the GHOST device somewhere in the house. The device is a valuable piece of technology that could be misused if it falls into the wrong hands. Shane has to keep the kids safe from assassins who are after the device, all while winning their trust and affection.
As the plot unfolds, Shane gradually gains the trust of the kids thanks to his dedication to their safety and his willingness to go out of his way to help them. He helps Zoe land the lead in the school play, teaches Seth discipline and the value of teamwork, and helps Peter overcome his stage fright.
Meanwhile, Shane also battles the villains who are determined to retrieve the GHOST. Shane tracks them down, uses his SEAL training to fight off their attacks, and ultimately saves the day.
In the end, the Plummers and Shane form a strong bond, with the family coming to appreciate and respect Shane for his bravery and dedication. The movie ends with a cheerful family dinner and Shane receiving a medal from the Navy for his service.