While on their vacations, each of the team receives a clue from a psychopathic killer challenging them to save his next victim.
Mr. Eko has dreams about his brother leading him somewhere. He seeks Locke's help in finding a secret location, the "question mark." Meanwhile, Jack and the other survivors grapple with the horrific situation in the hatch with the death of Ana-Lucia and Libby clinging to life.
The girls uncover a secret conspiracy of parents brainwashing their children into becoming model teenagers. And things get a lot worse when Alex falls directly into the trap, leading Sam and Clover on a mission to save her! In the b-story, Jerry gives the girls a car called NPU 3000. Villain: The parents of the brainwashed children.
J.D. feels that the same things happen over and over again at the hospital. Dr. Cox returns to work, but Elliot believes that he has lost his usual confidence. Elliot calls Dr. Cox on his behavior. Carla gets fed up with Turk, because he still can do a lot of stuff, but she can't since she is now pregnant.
Denny once again goes head-to-head with his non-son, Donny, when he shows up in his new role as a Lawyers Without Borders representative. But Alan finds it difficult to support Denny's defense when Denny makes light of the case. Meanwhile, Marlene Stanger, known as "The Squid," is hired at the firm, and immediately attracts Alan and repels Denise.
When an eight-year-old propositions a male classmate, Stabler and Tutuola are called in to investigate the case and soon learn that Jake Winnock's father spent seven years in prison for molesting his older brother, Teddy. D.N.A. tests clear Gregory Hensal of abusive his son, but implicate Jake's older brother, whom detectives soon learn has been running his own personal Internet pornography site. T.A.R.U. tech Ruben Morales joins the detectives in their search for Teddy after he goes missing, but his own guilt about his nephew's molestation after being raped by an online predator he met using the computer Morales had given him colors his judgment when dealing with one of the suspect's.
After discovering the true perpetrator of the bus crash, Veronica is desperate to warn others before it's too late. However, she inadvertently puts herself and her loved ones at risk in the process. Meanwhile, Keith tracks down Woody in hiding, Wallace leaves for Paris to be with Jackie, and Weevil again runs into trouble with the law.
Rory throws a graduation party for Logan, but their time together is bittersweet. Lorelai delivers an ultimatum to Luke.
After Bob gets his cover blown in Africa, he tells Jonas to cancel a visit a dignitary is taking to the area because of the danger. However, the official refuses and something shocking is quickly learned about why he really wants to go there. Meanwhile, Kim has an encounter while at the radio station and Molly gets offered a real estate opportunity.
Keith Soto returns to the base for a reunion and it's quickly discovered by Jonas and Col. Tom Ryan that he is a newspaper reporter who is writing an article that will expose the Unit. Jonas decides there is only one way to get him to not print the story. Meanwhile, with some help from Tiffy and Kim, Molly tracks down the woman who scammed $40,000 of the women's investment fund.
A young mother has a seizure while bathing her newborn son and nearly drowns him. House and the team have two cases at one time as they try to save the infant and determine the cause of the mother's seizures.
While working on an assignment, Gibbs is seriously injured in an explosion, and taken to a hospital, where he recalls his painful past, which he has always hidden from others. The rest of the team must proceed with the investigation and put their feelings towards Gibbs's injury aside. Tony is left in charge, which may cause a bit of trouble.
Jack searches for a safe place to land the plane when Logan gives orders to shoot it down. Hayes readies Bierko for a transfer to a secure facility, while Audrey receives some good news about her father. Logan becomes desperate as his plans start to unravel, but an unexpected ally at CTU turns the tables in his favor.
A girl from Jake’s school invites him to his first boy-girl party. Charlie and Alan help him get ready for it by giving him advice. Alan and Charlie get nostalgic and remember their first boy-girl party.
When a matchmaking company calls Ted claiming they have found his soul mate, he is forced to postpone his date when Lily asks for his help.
Everyone's ready to make their escapes across the high wire. Veronica and Nick realize they may be in over their heads. And Agent Kellerman helps Vice President Reynolds calm down before her debate.
Christine's former marriage counselor comes into the gym, leading to some awkward moments between the two women. When Christine mentions this to Richard, his cryptic reaction leads her to question whether it was in the counselor's best interest to encourage their divorce. Meanwhile, Matthew finds Christine's wedding video in a box of old photo albums, and Christine takes a trip down memory lane.
Allison is busy investigating the death of a local doctor when a man claiming to be "Death" begins appearing in her visions, causing her to worry that maybe her time on this world is nearly over.