It's Thanksgiving time in ‘the O.C.' It's time for family reunions, and Ryan gets called home by his family. Is it because of the holiday, or is it for a favor? Marissa decides to go along for the ride, but ends up going down Ryan's bad-memory lane instead. Seth plays the player role, but not very well.
Lex locates Morgan Edge and gets him to admit to dirty dealings with Lionel, but before Lex can take it to the authorities, someone tries to kill him at the mansion. Barely surviving, Lex flees and asks Clark for help. However, when Clark returns to the mansion to investigate he finds nothing amiss, and begins to wonder if it really happened, especially after Lionel announces Lex has had a psychotic break and must be institutionalized.
When Trip suffers a catastrophic injury, his only hope for survival is a transplant from a "mimetic symbiont" which Phlox grows from one of his exotic creatures.
A new student, Gary Harrison, joins the 4th grade. Gary is a Mormon from Utah. The children decide he needs to get his ass kicked, and they choose Stan to do it. After an awkward exchange of words, Stan is invited to Gary's house, where he learns all about Mormons.
Michelle is torn by personal and professional obligations when she must take charge of CTU after Tony is wounded. Kyle and Linda are captured by Hector's men. Jack and Palmer have a secret conversation, leading Jack to take drastic action in the face of the Salazars' threat. But Jack's plans are complicated when Chase gets in the way. Anne pushes Palmer back onto moral ground in the face of her ex-husband's blackmail scheme.
This episode demonstrates the production processes for prepared mustard, violins, nuts and bolts, and toilet paper, and shows how each is made.
Emily realizes that Richard has been secretly meeting someone for lunch for years. Lorelai accepts an invitation to dinner.
After fighting with his father and Haley, Nathan succumbs to the pressure he is feeling and takes amphetamines to help his game. However, he isn't prepared for the destruction the drugs do to both his body and his family. Meanwhile, Peyton goes to Lucas to rekindle their relationship, but when she arrives at his house, she catches him with Brooke.
A decomposed body is discovered in a tub of acid at a naval base and Ducky and Abby learn that the victim was a submariner. Gibbs discovers that there have been no reports of a sub crewmember missing, so he deduces that one of the subs has an imposter on board. With this new information, the team must find out which sub the man posing as the victim is in and what intentions he may have towards the sub.
Cate persuades Rory to try out for basketball because that would've made his dad proud.
Cheryl cajoles Jim into attending a couples cooking class, which turns into a disaster, so she lets Jim pick out the next couples activity – paintball.
Lilith comes to town for a one-day conference. She and Frasier try to get together, but keep having to cancel. Lilith discusses her romantic problems with a colleague at Cafe Nervosa before having to return to the conference.
A subway commuter is found castrated and bleeding profusely, leading the detectives to discover their "victim" may be the perpetrator in abducting women and forcing them to live in his dungeon for several years as his bride. As the detectives prepare to arrest their victim turned suspect, Benson arrives to find him murdered.
When another woman is murdered by the serial killer, the detectives arrest a suspect... and discover the killer's identity; and expecting a baby, Sipowicz and McDowell decide to get married.
WYNX has a new producer named Geraldine. Geraldine has fired the old producer Hank and hired a new sidekick named Holly to help Flex out with the Flex Files to increase ratings. Holly at first seems like a dumb blonde, but she later on proves her inelligence to Flex as she proves that her ""dumb-blonde"" act is just a tease she uses to help get more viewers. Meanwhile Duane finally meets his father, but it turns out that he's only come because he needs Duane's kidney. Also Breanna tries to figure out who Arnaz lost his virginity too, while Spirit works on a unique design to get her way into a fashion college.
Dr. Brown courts Linda Abbott despite Edna's and Harold's insistence that he's wasting his time, but Andy persists, forcing Linda to tell him that she is H.I.V. positive. Bright tells Ephram he can win Madison's affections by ignoring her, but the plan goes awry when she breaks up with her boyfriend. Amy meets a flirtatious and attractive town bad-boy, Tommy Callahan (guest star Paul Wasilewski), whose compassion for her problems touches her heart for the first time since Colin's death.
Horatio is driven to find his brother's killer and protect the niece he never knew existed when a woman shows up with Ray's illegitimate child. The team explores a voyeuristic Internet site in connection with a stockbroker's murder.
Spencer's cousin Chauncey begins working in the mail room at the record company and blabbing everyone's secrets. He recalls the time in college that he walked in on Spencer and Mona apparently in the midst of a drunken tryst, creating friction between Spencer and Camille. The story prompts Mona to confront her feelings for Spencer, as she wonders if the reason she has been so jealous of his girlfriends is because she wants him for herself. Meanwhile, Dee Dee creates a mold of her mother's pregnant belly--which Big Dee Dee hates.
Joan's enthusiasm about her new engagement is tempered when she learns that Brock doesn't want to have children, but she decides to relax and just focus on the immediate future. However, the issue continues to gnaw at her. Brock explains that, although his behavior may seem selfish, he believes it is wrong for someone to have children that they don't truly want. Joan tries desperately to change his mind; but he insists that they could be around kids by playing an active role in the lives of the children of family and friends. Joan ponders this for a while, but ultimately decides that she wants to have children of her own. Brock insists that they can have kids, but Joan fears that he would grow to resent her. They have a tearful break-up. William, determined to beat Joan to the altar, proposes to Lynn. He promises to support her financially and let her live at his place. Lynn learns that Joan and Brock have split, but keeps it to herself until after she has married William. Me