The first season of the new 90210 looks at life through the eyes of Annie Wilson and her brother Dixon, whose first day at West Beverly Hills High School leaves no doubt they’re not in Kansas anymore.
In part one of the series premiere, Harrison Wilson accepts the job position as principal of West Beverly Hills High, forcing the Wilson family to relocate from Kansas to California and adjust to new life in the city - all while keeping a close watch on their troubled grandmother Tabitha.
In part two of the series premiere, Dixon must deal with jealous teammates on the lacrosse team and Annie is dumped by her boyfriend back home but soon meets a potential love interest.
Harry and Debbie plan a family bowling night, but find their plans interrupted by the unexpected arrival of Annie and Dixon's friends. Meanwhile, Annie finds herself torn between Ethan and Ty, Naomi experiences a difficult evening with her father, and Kelly and Silver learn that Jackie's drinking is beginning to spiral out of control.
Annie, Harry, and Debbie are surprised to find out that West Beverly's theater director can't direct the school musical anymore. Kelly persuades Brenda to take over as the play's director, but they end up arguing over Kelly's involvement with Ryan. Meanwhile, Dixon tries to get a part-time job at the Peach Pit and Naomi confronts her father's mistress.
As the opening night of the school play "Spring Awakening" approaches, Ty reveals to Annie his plans for a one-on-one after-party in his hotel room with her. Others at school are concerned about how fast Annie and Ty's relationship is developing. Meanwhile, Naomi won't accept her parents' divorce and Adrianna is confronted about a substance abuse problem, which gives Annie a chance to be the lead in the play.
When Debbie is given the opportunity to shoot a fashion show for Nylon Magazine, Annie uses the event for a school project. Naomi tries to use the shoot to mend her parents' marriage, but her plan ends up backfiring. Meanwhile, Kelly receives a phone call that changes her relationship with Ryan.
Annie and Ethan get paired up for a class project where they must take care of a baby. This time together forces them to see each other in a new light. At Silver's half-birthday party, Silver and Dixon continue to get closer. Meanwhile, Harry and Debbie must deal with Harry's past when Tracy tells Harry that she's hired an investigator to find their son. Elsewhere, Ryan tries to cope with Kelly leaving and decides to try online dating.
After recuperating from her health scare, Adrianna returns and tries to make amends with Naomi, but her ex-BFF refuses to forgive her for the betrayal. Adrianna makes a surprising connection with Navid, who helps her through her situation. Meanwhile, Annie and Ethan finally take their rapidly growing romance to a new level during the school's homecoming dance, causing Naomi to feel jealous.
Harry and Debbie reveal to Annie and Dixon that Harry had a son who was given up for adoption 22 years ago. Meanwhile, Silver has the girls over for a girls' night, but the simple night together quickly escalates into a house party.
Noami grows spiteful as Annie and Ethan grow closer, causing her to deliver an unwelcomed surprise at Annie's sweet 16 party. Meanwhile, the school is all buzzing over the news that Ryan was given a leave of absence, and Adrianna discovers Navid's secret.
Brenda and Kelly's friendship takes a turn for the worse. Meanwhile, Sean moves in with the Wilson family, Naomi hangs with a new crowd, and Silver becomes jealous when a cheerleader pays a little too much attention to Dixon
Brenda receives life changing news. Meanwhile, Dixon grows closer to Christina, and an unexpected secret is destined to rock Adrianna's world.
Debbie and Tabitha clash after Tabitha surprises Annie and Dixon with a new car. Adrianna begins to open up to Naomi about her secret. Meanwhile, Silver and Dixon spend the day together at the beach, but things take an awkward turn when Dixon says three little words.
Adrianna must cope with her decision about her baby and her baby's father and turns to Naomi and Kelly for support. Ethan helps Annie prepare for the school play's try-out and are shocked to find out that Ty is also auditioning. Meanwhile, Dixon asks Debbie for relationship advice.
Adrianna tells the baby's father and her mother that she is pregnant. Meanwhile, Annie feels threatened by Ethan's friendship with Rhonda; and Silver finally opens up to Dixon.
Naomi meets an intriguing mystery man at her new home; Silver's Valentine's Day surprise falls apart, but she and Dixon still manage to come together. Meanwhile, Annie's jealousy of Rhonda starts to wear on Ethan.
Liam displays his dark side to Naomi, who is stunned but captivated by the intense, handsome bad-boy. Meanwhile, Annie and Ethan face another bump in their relationship when Adrianna makes it known that Ethan and Rhonda shared a kiss, and Silver and Dixon make a video that stirs quite a controversy at West Beverly Hills High.
When Dixon tries to slow down the pace of their relationship, Silver takes a trip to Kansas to learn what he was like before coming to Beverly Hills. Unfortunately, her fragile mental state gets her involved in a difficult situation. Meanwhile, Kelly once again faces her troubled mother Jackie.
Kelly and Silver are shocked when Donna arrives in town. Annie and Dixon take a road trip to visit someone from Dixon's past while Ethan spends his spring break working for Habitat for Humanity. Naomi also decides to work for Habitat when she learns that Liam will be there.
Now that they have finally sold their home in Kansas, Harry and Debbie have a yard sale, Beverly Hills-style. Meanwhile, Donna talks to Kelly about her separation, and later search for a place for Donna to open a clothing store; Dixon helps Silver in her recovery; Liam and Ethan's unlikely friendship continues; and when a scandal involving Naomi's father comes to light, her trust in Annie begins to falter.
Naomi's older sister, Jen, unexpectedly returns to Beverly Hills. Meanwhile, Naomi persuades Annie to go on a double date, and Adrianna and Navid reveal their decision to his parents.
Following their engagement, Navid and Adrianna celebrate their respective bachelor and bachelorette parties. While Adrianna feasts with friends and family at the Wilson home, Navid and the boys spend a wild night with college girls at a burlesque club. Meanwhile, sparks fly between Ryan and Jen, and Dixon continues to feel unappreciated by Silver.
With prom night quickly approaching, Annie, Adrianna, Naomi, and Silver get glammed up by a famous stylist. A dateless Annie agrees to attend the event with the extremely nerdy Charlie, who is massively crushing on the popular girl. But when he realizes that her interest is purely platonic, a furious Charlie plots an evil revenge. Meanwhile, Dixon is nominated for Prom King, Ethan gets accepted into lacrosse camp, and Kelly and Harry work to get Liam on the right track.
Adrianna and Navid are forced to make an impromptu exit from the prom when Adrianna goes into labor. Dixon confronts Ethan about Silver when he notices that Ethan might be developing feelings for his girlfriend. Meanwhile, Annie reaches the breaking point when Naomi accuses her of trying to hook up with Liam, and some of her peers (still angry about the after party fiasco) decide to take both verbal and physical action against her.