Maggie Cartwright appears to have simply walked away from every thing in her life, having left everything of hers behind. Later a ransom note appears on her mother's email list demanding a million dollars for her safe return.

Eleven-year-old Gabe Freedman is separated from his father on the subway to Yankee Stadium.

Four different witnesses claim that a woman was abducted from a mall parking lot while her husband was standing just yards away with his back turned to her.

Nineteen-year-old model Eve Cleary disappears and it turns out that there are very few people who actually knew her.

After telling his mother, he wanted to leave school for good, seventeen year old Andy Deaver vanishes from his private boarding school, last seen by it's headmaster, Graham Spaulding.

Patrick Kent, a Vice-President of a New York investment-banking firm, vanishes from a San Diego airport, only leaving behind two empty suitcases.

Abby, the three-year-old daughter of ADA Angela Buckman and her NYU lecturer husband Matthew, vanishes while in the park with her nanny.

After a confrontation with a local bully, foster teen William Hope disappears leaving his job at a burger restaurant late at night.

Third-year-resident Anwar Samir vanishes from the hospital he works in. Because of his Saudi-Arabian background, suspicions of terrorist links arise.

When a man leaves his home in the morning with his daughter to take her to school and then to open his dry-cleaning store, but they both of they never make it there .

Annie Miller disappears on her way to school. The group looks into her disappearance, with their suspects ranging from the local mayor, to Annie's godfather, all the way to a young man working for the father of her best friend. Twenty-four hours after Annie's disappearance, her best friend Siobhan Arintero also vanishes, leaving only a collection of videos to help find the two girls.

Jack and the team search for a pregnant woman, Kathy Dobson, who disappeared from a hospital before being told that she has serious complications. As the detectives race against time to find Kathy, their investigation gradually reveals that Kathy's seemingly happy life actually hasn't been going very well. She is eight-and-a-half months pregnant and, under the tight control of her husband Paul, has withdrawn from her family and friends. Paul's brother Ritchie, who has been following Kathy and providing Paul with addresses she visits, lists a woman who may be affiliated with an ""underground railroad"" that helps battered women. When the team members find the woman, they learn that she has been assaulted by Paul—but she still refuses to lead them to Kathy.

Chet Collins has been searching for his son since the boy was kidnapped four years earlier on a camping trip, and is the one case that Jack has never been able to forget. When Chet disappears, leaving behind only his wedding ring and the mountains of debt he had accumulated in his search, Jack will go to any lengths to find Collins and save him from himself.

The team investigate a disappearance of a flight attendant who may have been having a relationship with one of the pilot's.