At the opening day of the new school year, Brenda becomes peeved when Dylan starts spending time with the new transfer student Emily Valentine, while she and Brandon also have eyes for each other. Meanwhile, David is reunited with Scott after he returns from his summer vacation in Oklahoma and finds that his friendship with David isn't as close as it used to be.

Brandon and Brenda's handicapped cousin, Bobby, visits the Walshes and a mutual attraction between him and Kelly is complicated more by others assumptions than by Bobby's wheelchair. Meanwhile, David tries asking Donna out on a date. Brenda finally gets her driver's license on the third try, but is hesitant to drive Brandon's car. Also, Emily joins the school newspaper just to be near Brandon.

After Brandon inadvertently tips the school to Andrea's non-district residency after her success in a new article competition, she must move into her grandmother's apartment to prove she lives within district to avoid expulsion from West Beverly. But Andrea's problems only get worse when her grandmother tells her that she will not lie if questioned about Andrea's residence. Meanwhile, no one can convince Steve that his new girlfriend, Christine, is a gold-digger out to get his money.

The gang attends a Halloween costume party at an old brownstone mansion with Steve playing Zorro, Donna dressed as a mermaid in which the costume limits her mobility, and Brenda and Dylan going as Bonnie and Clyde. But the party is highlighted by Kelly's very revealing bewitching costume, but low-lighted when one student makes an unwanted advance on her. Meanwhile, David skips out on the party to meet with Scott where they reminisce about the "good old days" while waiting for an egg fight with some neighborhood kids that never materializes. Also, Brandon and Emily take her twin niece and nephew out trick-or-treating where a real scare begins when they lose the twins.

On Scott's 16th birthday, his mother gives Donna and David the responsibility of rounding up people for his birthday party to save it from being a social disaster.

Emily leads the gang to an underground nightclub where she attempts to show Brandon the ultimate pleasure with drugs after she puts a hallucinogen in his drink, with disastrous emotional and financial consequences for him when they are forced to flee from a police raid only to leave Brandon's car behind which gets stripped and ripped apart. Meanwhile, Kelly and Donna worry about David who gets drunk at the rave, while Steve and Andrea get lost in the inner city looking for the rest of the gang and driving to the wrong place each time.

Emily refuses to accept the fact that Brandon no longer wants to see her. She slashes her own tires and pretends that her parents are out of town so that Brandon will invite her to stay over. She sneaks into his bedroom and tries to seduce him. After he makes it clear that he is not interested, she begins to stalk and harass him by making crank phone calls. Andrea also discovers that Emily is the person who has been sending menacing letters to the school paper. Eventually, Emily shows up at Brandon's house and douses the gang's homecoming float with gasoline. Brenda and Dylan find her sitting on the float with a lighter, but Brenda is able to calm her down. Emily agrees to seek help. Meanwhile, Brenda and Dylan attend cultural events because she fears they spend too much time making out.

Steve arrives in Albuquerque, New Mexico and tracks down his grandfather, Al Brown, a diner owner. Al explains that his daughter gave up Steve because she was very young and wanted him to have a good home. He sadly reveals that Karen Brown died in a car accident many years ago. Steve leaves flowers at her grave, and convinces an eccentric Santa-like charter pilot to fly him home for Christmas. Back in California, Cindy is depressed about her first Christmas in Beverly Hills. She invites the kids' friends and their families for Christmas Eve dinner, but everyone has other plans. Brandon visits Emily in a psychiatric hospital, where she is doing very well. Meanwhile, Brenda begins work at an upscale clothing store. A mysterious old man steals a Santa Claus suit from Nat at the Peach Pit, and later shows up at the boutique store where Brenda works. She feels bad when her brass boss throws out the cheerful old man. After work, Brenda stops the police from harassing the old derelict wearing the Santa suite and invites him over for dinner, much to the wariness of Jim and Cindy. Also, Dylan goes to see his father in prison, and talks with the same Santa. Elsewhere, Kelly's mother, Jackie, is furious when David's father, Mel, backs out of Christmas Eve plans because his estranged wife asked him to come over with David. Samantha, Kelly, Jackie, Andrea, David, Mel, Donna, Dylan, and Steve all show up at the Walsh house for dinner and caroling. The old man in the Santa suite gives everyone presents and describes his lonely life: his children are grown and his wife died a year earlier. He thanks Brenda for her kindness and generosity, then mysteriously disappears as footsteps are heard on the roof.

After mistaking a woman at a rural filling station for his former girlfriend Emily Valentine, Brandon decides to visit Emily's home in Marin County north of San Francisco. He learns that the Valentines have moved to Greece, but runs into Emily by chance on a cable car in San Francisco. They rekindle their romance and decide to spend Thanksgiving together, but Emily does not reveal that she must move away in a week. Back in Los Angeles, the KEG frat house and Alpha sorority serve Thanksgiving dinner at a halfway house, and John Sears tries to take advantage of a 15-year-old girl. Steve intervenes and has the fraternity president distract John. Meanwhile, Dylan declines Kelly's Thanksgiving invitation because he plans to go surfing, but later agrees to dine with the Walshes. When Kelly comes over with her family, she snaps at Dylan and makes a scene. Elsewhere, Andrea is hesitant to attend a Thanksgiving soirée at the home of Dan's parents. Jesse, the bartender from the Walshes' anniversary party, is working Dan's parents' party; he asks Andrea out, and she willingly gives him her address.

Emily has been accepted to the prestigious Cousteau Institute in France, but does not want to attend because she and Brandon are in love. Brandon observes her passion for marine biology and encourages her to pursue her dream. Brenda balks when she is asked to appear nude in an experimental campus play. The frat and sorority pledges must endure a series of humiliating experiences during "Hell Week." The upperclassmen order Steve to steal a prize autographed baseball from Professor Randall for a scavenger hunt, but he gets caught. Andrea breaks up with Dan and begins dating Jesse. She learns that he is a UCLA law student who attended undergraduate courses at Yale.

Emily flies back from Paris to attend a seminar at La Jolla. She asks Brandon to meet her at the airport, claiming to have just a four-hour layover. She actually has a week until the beginning of her seminar, but Brandon breaks her heart by revealing that he is dating Kelly. When he sees her back to her hotel room, they share a passionate kiss. Steve and Griffin organize a holiday rave at an abandoned house. Valerie helps them out in the hopes of getting back in Steve's good graces. David and Clare accidentally post the notice about the event on a computer bulletin board for lesbians, who constitute most of the guests. The house has very poor wiring and continually blows fuses. Griffin uses too much electricity, and the house catches on fire. Ray rescues Steve and Valerie, who were fooling around in one of the bedrooms. Kelly and a girl named Allison are trapped in a downstairs bathroom with no means of escape. The firefighters try to reach them as they are engulfed by flames.

In the aftermath of the house fire, Kelly suffers second and third degree burns on right wrist, ear, and the whole right side of her neck. Allison's injuries are much more severe, but she maintains a positive attitude. Brandon is racked with guilt because of his feelings for Emily. Kelly does not react well when she learns that Emily is still in town. She calls Dylan to discuss her insecurities and Brandon visits him in search of advice. Kelly believes that Brandon is only staying with her out of guilt, but Emily eases her mind when she reveals that he expressed his love for Kelly before the fire. Meanwhile, Steve feels guilty for the house fire and calls upon his father, Rush, to help out. Griffin's father hires an accomplished attorney for Steve and Griffin where Rush advices both to plead guilty to criminal trespassing in order to avoid jail time. Steve and Griffin receive two years of probation and community service... and are forbidden from operating dance clubs or parties for two years. Steve is furious to learn of this provision, especially after he discovers that Griffin in fact stole the keys from his father's real estate office to the house, rather than obtaining permission to use it for the rave. Steve tells his father that he didn't know about what Griffin did, but Rush (being more arrogant and narrow-minded) refuses to believe Steve and tells him not to ever call on him again for help. Afterwards, Steve physically attacks Griffin and orders him to leave the fraternity. Elsewhere, Ray's perpetual bad mood confuses Donna. He explains that his mother always begins drinking around the holidays, as his drunkard father left her on Christmas... after pushing her down the stairs and causing her to have a miscarriage. Andrea and Jesse throw a party for Hannah's first Hanukkah. Jesse obtains work as an attorney for those who cannot afford representation. He is frustrated by the court treatment of a single Mexican immigrant father, whose kids are taken away when a babysitter neglects them. At the end, Dylan comes home from rehab and is greeted by a letter from a stranger who found Erica's bathroom note pleading for his help.