Sam agrees to do a favor for a friend by looking into the identity of a young amnesiac who was found wearing expensive clothes by two police officers. The investigation leads them to a play the woman was involved in and a mugging gone wrong, then they follow the trail to the woman's past, which seems to have been the trigger for her amnesia. Jack takes some time off work to deal with his father, who is getting worse as his Alzheimers begins to take over and his kidneys fail. Jack finally convinces Frank to seek help, but it's too late, and Jack has to say goodbye to his father.

When Leah Robinson goes missing after a confrontation with a young man at an art gallery, the team mvoes in to investigate and soon become suspicious of Leah, suspecting her of murdering young women that she believed to be involved with her husband, Ken. Ann isn't quite ready to take her romance with Jack public, and their relationship gets rocky when their different methods of handling the case tip off the suspect.

After attorney Jennifer Nichols disappears, the team investigates the last few days in her life and soon find that she had grown disillusioned with her most recent relationship with Allen Davis. Discussions with a married ex-lover reveal that Nichols had recently gone through an old case file relating to a ten-year-old bank robbery, which has a connection to her recent relationship. Jack and Ann avoid discussing a recent development in their relationship -- her pregnancy.

The team investigates when Aaron Gibbs ends up missing one night and soon learn that he had been lying to his wife about quitting his job, and had been working nights in a fight club. During the course of the investigation, Jack and the others learn that Aaron's disappearance was connected to events that took place during Hurricane Katrina, when Aaron was fighting to save his sons, and follow the trail of evidence, believing that the events of that night in New Orleans hold the key to finding the truth about the missing man.

Wendy Kim goes missing during her shift at the family deli, and the team gets involved to find out what happened to the young Korean woman. It isn't long before they learn that Wendy had recently broken off an engagement to a young Korean man her parents were very supportive of, and that she had recently been doing a lot of on-line dating and had gotten herself involved with the wrong kind of men, including one who wouldn't take no for an answer.

Cindy Peterson, a mother who had become a stripper to support her family, goes missing after work one night, and Jack sends Elena in undercover at the strip club to learn what she can. Danny moves in to keep an eye on her after someone catches on to her spying, while Vivian discovers that Jim Peterson hasn't been completely honest with them. Jack faces censure from Olczyk over his relationship with Ann, and is angry with Ann after she admits to him that she thinks he let their relationship cloud his judgment in the Davis investigation.

The team searches for Chris Manning, a family court judge with a soft side who went missing after meeting with a young boy caught between his mother and his abusive father. Suspicion initially turns anyone Manning may have riled up due to his court rulings, but after his clerk is shot in what appears to be an attempt on Manning's life, the team learns that the secret behind Manning's disappearance is tied up with something that happened over twenty years earlier.

Five people with an odd connection go missing from a coffee shop, and the team determines what the connection had to do with their disappearance. Meanwhile, Samantha gets ready for the birth of her child.

The team discovers a long festering secret which sets off a deadly chain of events when they investigate the disappearance of the teenage son of a Secret Service man.

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.

Max Cassidy vanishes after leaving a message on his wife's voicemail, with both Jack and Ann frantic to find him. While investigating, Jack realises that Max was having an affair, and that he's gotten much deeper into a case than he should have following the murder of his partner, Jimmy, a man Max had felt was too green for undercover work. Both Jack and Ann fear the worst as the team tries to hunt down Max.

Megan Sullivan is H.I.V. positive, pregnant and missing. Initially the team suspects that her husband, who seemed to be less than thrilled about the baby, is involved, but soon learn that Megan had received a call from a prison, and their search tracks them to a former lover, who gave her H.I.V., her husband's former mistress, who had seen her taking part in a tense conversation not long before she vanished, and her own H.I.V. specialist, who had recently given her bad news. Martin thanks Danny for his help, and tells him that he is continuing to seek counseling for his addiction.

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.

A high school student goes missing after leaving her prom early to get some rest in her hotel room, leaving behind a bloody dress and a lot of questions about what may have happened to her.

John Michaels is a 71-year-old insurance investigator who went missing after last being seen getting into a car with two strange men. While investigating his disappearance, the team finds that he had recently tried to make amends with his ex-wife and has been trying desperately to get his older daughter on the straight and narrow. Things get strange in the case though, and all is not as it seems.

After a young woman named Agnes Deschamps goes missing, the team takes a look into her disappearance and learns that the young woman was believed to be a psychic. Sam has trouble accepting that one of their witnesses purports to be a psychic, although she is thrown when the woman correctly points out her problems with Martin. Jack, Martin and Danny pick up the extra hours with Vivian out awaiting heart surgery and together the team manages to track the young woman down after a supermarket parking lot kidnapping yeilds an unlikely clue.

A man, whose daughter went missing years ago, also goes missing, and the team tries to connect his desire to help another couple missing their son. Meanwhile, Jack is trying to adjust to his new boss, Clark Medina.

When a spoiled heiress in her early twenties is kidnapped, the team has to work against the clock to save Chelsea, who is being featured on a website giving fans the option to choose whether she lives or dies. As they continue to investigate her disappearance, the team learns that Chelsea had finally been starting to grow up, but she may not have time to enjoy her new life.

When a priest disappears Jack begins to think that the man is involved in some wrongdoing rather than the possible victim of a crime.

When a 14-year-old violinist disappears on the night of a concert, the team follows her and her valuable violin's trail and Samantha bravely tries to recover from the gunshot wound.

The team Search for a missing motivational speaker only to find that there is an abundance of suspects,The find out that they man is no who he appears to be.

The team Looks for a college football coach who goes missing after being fired for his role in the team's dismal season performance,but the investigation soon uncovers that the Coach new policy of suspending players who have academic and behavioral issues caused the football team to repeatedly play without its main players and suffer defeats due to this rule. As a result of this, The team begin to suspect that it was some of the angry players, or members of the school administration and even a high-stakes gambler who all are facing financial losses resulting from the teams losing streak. Meanwhile, Malone must make a difficult decision when his wife surprises him with her strong desire to relocate their family to Chicago, where she has just been offered a superb job opportunity

This time, the team searches for a delusional appearing Sci-fi fanatic who disappeared from his appartment after ranting on about those ""out to get him"" (before peeling back the tinfoil covering his windows). Jack also has to deal with the consequences of his actions in the affair and how it affected the rest of the team.

When Ian Norville disappears on a field trip to a museum in Manhattan, the team gets involved, but it isn't long before Jack turns his suspicion to his father, Daniel, who soon admits that he didn't take the necessary precautions with his son, who happens to be autistic.