David seeks his father's help in winning over Felice. Mel and Jackie invite David, Donna and her parents over for dinner. Felice makes snide remarks about the pre-prom incident from four years earlier, the fact that Jackie and Mel are not married, and David's mental problems. A furious Donna refuses to come to her parents' house for Christmas. Felice apologizes to David and asks him to arrange a truce. Kelly's father fails to show for dinner, but a young woman arrives in his place. She stuns Kelly by revealing that she is her half-sister, Joy Taylor. Kelly is angry to learn that her mother hid the truth, and she and Joy become friends as they compare notes about their absentee father. Chancellor Arnold immediately hits it off with Samantha at his Christmas party, making Steve and Clare uncomfortable. The gang picks names from a hat to decide who will exchange gifts. Brandon and Tracy struggle with their gift selections, as neither wants to send the wrong message. While shopping for Kel

Rusty, a technician at the TV station, quits in anger after the police question him about Donna. Evan admits his feelings for Donna and confesses that he is the stalker. When she tells Brandon and Tracy, he pulls a gun and holds the entire staff hostage. He holds Donna at gunpoint and forces Brandon and Tracy to put him on the air. He eventually lets the others leave, but Brandon refuses to leave Donna. Donna tricks Evan into putting his gun down by feigning an interest in him. She kisses him, then kicks the gun away as the SWAT team moves in to arrest him. Val threatens to fire Tom unless he stops seeing Kelly. She apologizes, but he quits anyway. Kelly claims that she is not acting out of spite. Steve and Clare try to keep their parents from dating, as they are afraid of being left behind. They finally apologize after realizing how selfishly they have acted.

Brandon has to take care of Kelly and Valerie, who are both laid up with the flu. The girls discuss the reasons for their feud, which supposedly dates back to a time when Kelly interrupted a make-out session between Valerie and Brandon. Val blames Kelly for costing her the love of her life, while Kelly insists that she gave Brandon her blessing to date Valerie. Valerie is contacted by Derek Driscoll, a representative from Mr. Taylor's firm. Val tells Brandon that Kelly is hiding the fact that she was accepted to Columbia's graduate school. Kelly declares that she is not leaving town, and decides that Brandon should throw Val out of the house. David convinces Donna to join him at his business meeting in New Orleans, even though she has a class presentation the next day. David thinks that he will score, but gets no further than usual. They oversleep, causing Donna to miss her presentation. Samantha ignores Chancellor Arnold during an evening honoring her sitcom, and eventually dumps him.

Valerie and Noah are not enthused when David's song receives radio airplay. They express their discontent at the amount of time David and Donna are spending together. David and Donna lie about their whereabouts before embarking on a shopping trip. They get into a car accident; Donna injures her back and begins popping painkillers. Val encourages Noah to reach out to his estranged half-brother, Josh. Valerie and Noah believe that their mates are cheating on them and become depressed. Noah gets very drunk, and Josh furtively slips something into Valerie's drink. After Josh is distracted by a phone call, Noah takes Valerie to the office and has sex with her. Val awakens in a daze and feels extremely ill, despite the fact that she had only one drink. David takes her to a doctor, where test results find Rohypnol (the date-rape drug) in her system. David and Valerie race over to the boat and accuse Noah of rape. Kelly spends a romantic Valentine's Day with Jeff. He expresses a willingness to

Noah's civil trial begins. His attorney portrays Valerie as a golddigging tramp, and uses the gang's testimony to place Noah in a favorable light. Josh's testimony reflects very badly on Noah, and Val wins the case. Everyone apologizes to Valerie and turns against Noah. While rummaging through Josh's belongings in search of more pills, Donna discovers a prescription for Rohypnol. Josh admits that he drugged Valerie, and Noah offers to help Val build a case against him. David's record company experiences a shake-up. The new reprensentative forces Jasper out of the band and turns over all creative control to David. Jasper accuses David of treachery. Unable to meet her deadline, the disoriented Donna steals designs from a co-worker. Noah finds Donna passed out on her living room floor.

Music: ""This Ain't Going Away,"" performed by Jasper's Law; ""Keep It Together"" by Brian Austin Green

Lenny receives joint custody of his daughter. After he explodes in a rage during his first visit, Kelly decides to help Leah and her daughter skip town and assume a new identity. Lenny follows them, realizes what they are planning, and attacks Leah. Matt, bothered by a guilty conscience, helps Leah obtain the necessary identification to start her new life. Valerie elects to throw a massive rave as a farewell party before turning herself in to the police. David calls Abby to inform her of Val's plans, and she intercepts her daughter at the police station. She pleads with Val not to confess and offers forgiveness, insisting that she is to blame for not intervening on Valerie's behalf. Unable to communicate with Noah, Donna begins dating Matt. She hurts Matt's feelings by ignoring him during Val's party to tend to the inebriated Noah. Noah breaks a promise to Donna by skipping a court-mandated AA meeting and continuing to drink. Sophie tries her hand at waitressing after a disastrous phot

Donna is not seriously injured, and forgives Dylan for the accident. Dylan's friends encourage him to check into rehab. Kelly acts very pushy and suggests that Gina and Matt are responsible for Dylan's problems. Dylan sneaks out the bathroom window and attempts to go through withdrawal on his own. Kelly finds him lying on her doorstep and takes him to the hospital. Matt cuts a deal with the district attorney to keep Dylan out of jail, but isn't sure that he deserves another chance. Dylan goes into cardiac arrest and has to be revived through a defibrillator. Kelly realizes that she must back off and learn to respect Gina's relationship with Dylan. Matt receives a surprising call from a woman in New York. Donna designs a gown for a famous singer to wear to a nationally televised awards show. She fears that she is ruined when the woman looks like a wreck (with uncombed hair and garish accessories). However, the teenagers who emulate the singer soon flock to Donna's store. Steve gets into

Noah faces foreclosure after failing to make his mortgage payments on the Peach Pit/After Dark building. He accepts an offer from a restaurant owner willing to pay much higher rent, and decides to terminate Nat's lease. Noah ignores a warning from Dylan, who buys the building so that Nat can stay. Claudia reveals that her visa will soon expire; David vows to help her stay in the country. When a job offer falls through, David agrees to marry Claudia. As a promotion, Steve has a man dress up as a leprechaun and promises a ""pot of gold"" to the person who catches him. A butcher takes the offer seriously and demands a reward, then pulls out a knife when Steve is unable to pay. The man breaks down in tears and explains that his son needs heart surgery. The paper helps finance the operation, thanks to donations sent in by readers touched by the man's plight. Kelly and Donna clash when Kelly hires a public relations guru to attract more attention to the store.

Janet begins to panic about wedding preparations. Steve suggests that they organize a scavenger hunt for their friends, with clues providing the location of a party. Dylan and his friend Andrew are attacked by gay bashers. Andrew does not want to help put away their attackers because he has yet to come out. His boss finds out that he is gay and puts him on leave. Kelly snipes at Noah during the scavenger hunt, as she blames his strip club for Jackie and Mel's break-up. Gina freaks out when Dylan refuses to pull over and help a stray dog. David helps her find the animal and take it to the vet. The gang arrives at a park to discover that Steve and Janet are holding a surprise wedding ceremony. At the reception, Dylan baffles Kelly by commenting on how beautiful she had looked in her wedding dress. Gina leaves abruptly after Dylan admits that they will probably never get married. She sleeps with David. Kelly confronts Dylan about his remark. He confesses that he flew in for her wedding, o

Dr. Martin dies of a stroke. Kelly suggests that Gina is to blame for his death, as does the grief-stricken Felice. David also seems to support this theory. Gina is upset when the obituary states that Dr. Martin has only one child; Felice calls her a mistake. Donna feels that Dr. Martin would still be alive if Gina hadn't discovered he was her father, even though Donna was the one who shared this information. Dylan grows tired of Kelly's whining and moralizing. He and Gina decide to leave town. Gina is not allowed to sit with immediate family at the funeral. However, she goes to the front of the church and finishes the eulogy when Donna is unable to continue. Felice embraces her and accepts her as part of the family. Dylan decides that he shouldn't leave Los Angeles because he has unfinished business with Kelly. Gina says goodbye to Donna and embarks on a cross-country road trip. David comforts Donna throughout her ordeal. Kelly takes a public relations job to ease the financial burden

Special looks at the past 10 seasons of television series "Beverly Hills, 90210" through clips and interviews with current and former cast members.