The continuity was introduced in 1990 with the debut of Darren Star's teen drama Beverly Hills, 90210, which was produced by Aaron Spelling and initially aired on the FOX television network in the United States. After this series became a worldwide success in 1991, Star expanded the franchise with 1992's Melrose Place, a drama about young adults in L.A. which would also grow into a famous hit. The third series, Models Inc., has thus far been the least successful of the shows to air, having lasted only one season (June 1994 to March 1995).
The fourth entry, simply titled 90210, was the first show in the franchise to not debut on FOX in the United States. Developed by Rob Thomas, Gabe Sachs, and Jeff Judah, the series premiered on The CW Television Network on September 2, 2008.
The first series initially followed the teenage lives of several friends who attended the West Beverly Hills High School: Brandon Walsh (Jason Priestley), Brenda Walsh (Shannen Doherty), Kelly Taylor (Jennie Garth), Steve Sanders (Ian Ziering), Andrea Zuckerman (Gabrielle Carteris), Dylan McKay (Luke Perry), David Silver (Brian Austin Green), and Donna Martin (Tori Spelling). As the series progressed, several other characters were introduced at varying points.
Originally, the series centered around the culture shock of twins Brandon and Brenda as they adjusted to the new experiences and friends that awaited them upon their family's move to Beverly Hills. As the show progressed, however, it gradually became more of an ensemble cast drama, with equal attention given to the parental issues, academic dilemmas, career aspirations, and romantic concerns of the other characters. One of the series' early focal points involved an initially forbidden Brenda-Dylan relationship—along with a subsequent triangle involving Kelly. Other series milestones included the beginning of a long and complex relationship between Brandon and Kelly, the question of how long Donna and David's bond could endure without sex, and a rally organized on Donna's behalf in order to overthrow a school ruling against her.
Toward the end of the second season, the character of Jake Hanson—a tough but mellow biker who served as an older friend and mentor to Dylan—briefly arrived for a construction job at Kelly's house. The subsequent attraction that developed between a resistant Jake (Grant Show) and a willing Kelly led into the second series of the 90210 continuity.
Darren Star's next show, also produced by Spelling Television, followed the lives of several young tenants in an apartment complex. The relationship between Kelly and Jake was resolved over a series of episodes, with a persistent Kelly eventually letting go and returning to Beverly Hills.
Originally conceived as a lightly toned drama about the personal and professional lives of yuppies, Melrose Place began to change with the arrival of testy Amanda Woodward (Heather Locklear), whose conflicts with the generally strait-laced Alison (Courtney Thorne-Smith) over Alison's roommate Billy (Andrew Shue) quickly became the show's centerpiece. Also focused upon was the adulterous relationship between Dr. Michael Mancini (Thomas Calabro) and his colleague Kimberly Shaw (Marcia Cross), which was eventually discovered by Michael's wife Jane (Josie Bissett).
With the progression of the second season—which was highlighted by divorce, blackmail, revenge, character revamps, and much angst between couples—the show had begun to secure a reputation for darker, more extraordinary story lines. This kind of writing would become standard for the series throughout the remainder of its run.
Toward the end of season 2, a somewhat mellowed Amanda was reunited with her long-estranged mother Hillary (Linda Gray), the owner of a modeling agency. This development would provide a foundation for the franchise's third story.
Debuting in the summer of 1994, Models Inc. was produced by Spelling Television and created by Charles Pratt, Jr. and Frank South. The series followed the lives of Hillary and several of the disparate, ambitious models in the titular agency—women whom Hillary sometimes felt a maternal bond toward. Also present was Hillary's son David (Brian Gaskill), the loyal, valiant, and occasionally hot-headed vice president of the company. At the beginning of the first episode, actors Grant Show and Daphne Zuniga briefly appeared as their Melrose Place characters, seeing off a young model (Cassidy Rae) as she headed to the agency.
Unlike the previous two shows in the continuity, Models Inc. did not experience any significant changes in character focus or tone—choosing, instead, to explore the ensemble cast from the start and immediately present the kind of story lines that had made Melrose Place famous. The initial focus of the series was a mystery surrounding the murder of model Teri Spencer (Stephanie Romanov), who'd announced her intentions to leave the agency. For a number of episodes throughout the first story arc, suspects included Hillary, Teri's ex-boyfriend Brian (Cameron Daddo), Teri's rival Julie (Kylie Travis), and Teri's own sister Carrie (Carrie-Anne Moss). Once the killer was revealed, the characters moved on, with their focus switching to the arrival of Stephanie Romanov's new character Monique, a model who was a nearly dead ringer for Teri. The remainder of the series centered largely around the models' growing relationships with their boyfriends and each other, while also dealing with the issues of substance abuse and the pressures of the business. Primary antagonists included several figures from the past—including a stalker, a jealous sister, and Grayson (Emma Samms), the cunning and powerful ex-wife of Monique's fiance.
Models Inc. was cancelled in March of 1995. This series bears the distinction of being the only show in the continuity in which characters from the original have not appeared.
Premiering on September 2, 2008, 90210 is produced by CBS Paramount Network Television. The series acts in part as a re-imagining of the original series, following two siblings—Annie and Dixon Wilson (Dixon is adopted), played by Shenae Grimes and Tristan Wilds—who've recently moved to Beverly Hills with their family and enrolled in West Beverly High. Like Brandon and Brenda 18 years before, Dixon and Annie meet several new friends who compose the rest of the cast.
Among the returning characters is Kelly Taylor, who has appeared in a recurring role while serving as a guidance counselor at the school. Brenda also returned in a recurring part, reuniting with Kelly and directing a school musical.