Time Warner’s (TWX) HBO has enlisted the help of four writers to each create their own Game of Thrones spinoffs, the network confirmed to The Hollywood Reporter on Thursday. According to the report, each of the spinoffs will examine different time periods in Westeros lore, though HBO didn’t say exactly when or how they would fit into the Game of Thrones universe.

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However, showrunners are only planning two more seasons of the show that will span 15 episodes. The penultimate season will premiere on July 16, giving HBO one more year of the franchise before it needs to find a replacement.

Given the popularity of the franchise and HBO’s own admission that it would have liked to have had Game of Thrones on air for longer, it’s no surprise the company is considering spinoffs. However, it’s not immediately clear whether the spinoffs will be entirely new series, movies, or miniseries. HBO also hasn’t greenlit any of the spinoffs, so it’s possible nothing comes of the company’s investment.

According to The Hollywood Reporter, these are the four writers who have been charged with creating the spinoffs:

• Max Borenstein: Screenwriter for Kong: Skull Island and 2014’s Godzilla. Borenstein was also the showrunner for ill-fated Minority Report series.
• Jane Goldman: Screenwriter for Stardust and Kick-Ass.
• Brian Helgeland: Writer and director on the Jackie Robinson biopic 42 and Legend.
• Carly Wray: Writer on several former series, including Mad Men and The Leftovers.

Game of Thrones premiered on HBO in 2011. The series was created by David Benioff and D.B. Weiss and is based on the George R.R. Martin fantasy novel series A Song of Ice and Fire. After it premiered, the show became a smash hit and has since become one of the most popular franchises in HBO history.