Brandon becomes jealous of Andrea's new boyfriend, Jay, who invites her to Houston with him for a Republican convention, while she tries to get Cameron, to join on her day care group outings. Dylan's father, Jack, asks to put in a good word for him at his parole hearing, and Kelly keeps Dylan some company while mending her broken heart over leaving Jake Hanson (see Melrose Place). Meanwhile, Brenda and Donna arrive in Paris and they get a less than dazzling welcome to the City of Light after meeting brash students, as well as eating at a local restaurant.

Brandon, now dating Brooke, is troubled by the hard-luck story by a homeless man named Jack Canner. Dylan and Kelly teeter on the brink of a romantic affair. Steve pressures David to let him manage his music career after listening to David's demo tape. Andrea becomes alarmed when Cameron, her deaf student, goes missing. In Paris, Brenda pretends to be French to fit the assumption of a handsome American student named Rick who asks her for directions and becomes smitten with her.

Dylan and Kelly decide to keep their romantic liaison a secret when Brenda and Donna return from Paris. During a welcome-back party for Brenda and Donna, Brenda confides in a guilt-ridden Kelly that she sees that something has changed about Dylan while she was away. Meanwhile, Brandon discovers that Brooke is not the girl of his dreams after he sees little amusement in her repeated racist and stereotypical comments. Also, Steve finally lands a gig for David at the end-of-the-summer clambake at the beach club.

The day after New Years Day, Clare arrives at Casa Walsh from her Christmas stay with her father in San Diego and listens to the gangs New Years Eve mishap stories which include: Steve babysitting for his two rowdy teenage step-brothers, Ryan and Austin, whom sneak into the After Dark for some rowdy partying. David and Joe skip out on the After Dark party to help Donna peruse her escaped parrot. At the same time, the stress between Kelly and Colin over his drug use escalates to a point of him having Valerie hide his cocaine stash for him. Also, Susan's ex-boyfriend, Jonathan Casten, arrives in town which discourages Brandon when he learns Jonathan's true colors that he wants Susan back for himself.

At a frat party Steve hosts at Casa Walsh, things take a turn for the worse when Steve's two teenage half-brothers, Ryan and Austin, start drinking excessively in which Ryan passes out and almost dies from alcohol poisoning. When Rush finds out, being arrogant and narrow-minded as usual, naturally blames Steve for the near-disaster. Valerie brings Colin to the party, who's between incarcerations. Meanwhile, Tara gets out of rehab and moves in with Kelly, Donna and Clare at the beach front apartment. Also, Kelly invites Greg, a med-student from the rehab center, over to the party and whom ends up saving Ryan's life.

Carl hosts Steve's weekend long 21st birthday bash on the ship Queen Mary in Long Beach, where the music group "The Goo Goo Dolls" entertains. Carl then asks Steve a favor: to have a chance with Clare who he has had a crush on. David and Donna grow more intimate while their producer Erik, makes a move on Donna and other women as well. Andrea Zuckerman arrives in town to have fun at Steve's party, and Nat brings Joan along who keeps feeling unwell. Meanwhile, Valerie hires an FBI agent, named Richard Ballen, to find Colin who's in the area trying to get access on a ship to take him to South America. Also, Susan tells Brandon that she has decided to leave town to accept a job offer at a newspaper company in Washington D.C. which makes him wonder if he has a future with Susan after all.

At a reunion party at the Beverly Hills Beach Club, Clare is stunned after she learns of Steve's past relationship with Kelly, who learns there's more to the story than she knew. Meanwhile, Kenny puts a social spin on his business with Valerie, who once again throws romantic common sense to the wind. David's new friend, Mark Reese, needles Brandon into joining the college TV station. Donna meets an old high school friend whom she once has a crush on. Also, Steve's annoying stepbrothers, Ryan and Austin, return and learn another hard lesson in finding girls.

Kelly learns that her old engagement ring that Brandon bought for her years ago is the cause of the continuing friction between him and Tracy. Meanwhile, Donna can't decide whether to be with Cliff or David, while Chloe makes a move on David after she tells him that Donna is not the woman for him. Clare tells Steve to give one of his step-brothers, Ryan, an advance talk about the birds and the bees. Valerie finally confronts her mother and tells her the true, long-kept facts behinds her father's suicide which are: her father killing himself on the day Valerie and Tom threatened to go to the police with the fact that he's been molesting her. Also, Abby then flies back to Buffalo and Tom soon follows suit.

On the day before commencement, Kelly becomes determined to oust Valerie from the Walsh house (and town) and pressures Brandon to do so. Meanwhile, Donna decides it's time to move up to a new level of romance with David after getting advice from her grandmother. Steve plans to pull the "best senior prank ever" with some help from his frat brother Muntz, as well as David.

On the day of graduation, a broke and lonely Valerie disrupts Kelly's plans when she takes off on a mindless spree causing Brandon to delay the ceremony to look for her. Kelly's father, Bill, throws a 1920s nostalgic post-graduation party for the class and has the The Cardigans band perform. He also tries to make up with Kelly, who continues to push him away. Steve's stepbrothers, Ryan and Austin, show up for festivities where Ryan is drawn to Kelly's half-sister, Joy. Also, Steve's plans for Clare derail due to her decision to move to Paris with Chancellor Arnold, which leads to Steve and Clare breaking up for good.

Matt and Kelly aid Dylan in trying to help him find his father in which the search leads them to Arizona where they find Dylan's father, who lives under the alias Eddie Waitkus, and has a wife and young son. Meanwhile, Donna brings Noah at the beach apartment to convalesce for his injuries where he begins to take advantage her loneliness to make the moves on her. Janet becomes worried when Steve reverts to his old partying form when his stepbrother Ryan visits. Also, Camille tells David that she's beginning to resent Donna's constant phone calls to him for support which intrudes on their evenings out.

Jack McKay suddenly shows up at Dylan's front door of his hotel room where he makes him an offer to be a part of his life in which he will leave the witness protection program that he is in. But Dylan is approached by Christine Pettit who warns Dylan about a rash decision that his father is making since he is still a marked man by his former mob partners. So, Dylan tells Jack to go back to his new life in Arizona while he deals with his own. Meanwhile, Steve lobbies for Ryan's return to college who falls under the influence of Noah in bar-tending at the After Dark. David interviews for a radio job in New York City while Donna and Camille worry about this turn of events. Also, Matt reopens his practice after his suspension and his first client is a stand-up comic named Stuart Patton who's jokes are funny only to Matt.

After David proposes marriage to Donna, both of them contemplate the matter and finally make a big decision. With Janet's career as a junior editor for the new owner of the Beverly Beat taking off, Steve become conflicted about being an unemployed stay-at-home father for baby Maddy. Kelly, while trying to open her independent public relations company, must make her own final decision on marrying Matt to console him after he learns that his brother in New York has suddenly died, and an uncertain-of-himself Dylan after he gets his college diploma. When Kelly tells Matt that she cannot marry him out of uncertainty, he lets the slip about his one-night stand during the desert road trip. Also, Noah contemplates commitment to Ellen and her daughter, but when he feels he's not ready, he breaks up with Ellen for good.

David and Donna announce their engagement in which all of their friends rush to give them the perfect wedding with Donna's mother, Felice, and Kelly's mother, Jackie, taking over the arrangements and Nat catering for the ceremony and agreeing to escort Donna down the church aisle. Meanwhile, Steve asks Janet to help him form their own publishing company so they both can have time for baby Maddie. Noah returns to Ellen and tells her that he has decided to give their relationship a second chance. At Donna's pre-wedding party, Kelly, Janet, Felice and Jackie are in attendance as well as friends from their past who include West Beverly High principal Mrs. Yvonne Teasley, as well as Andrea Zuckerman and even Valerie Malone. At David's bachelor party, Steve, Noah, Dylan, Nat, and David's father Mel attend the gathering as well as Steve's stepbrother Ryan and former KEG fraternity brother Munz, except for Brandon Walsh who sends his regards to everyone via videotape. The day of the wedding goes without a hitch and at the end, Matt shows up briefly to tell Kelly that he has decided to move back to New York, and she goes back to try to renew her relationship with Dylan.