High School Musical 3 won't be hitting UK cinemas for months yet, but work has already started on HSM 4!
TV bosses said writing was under way, but it's not clear if HSM's biggest stars Zac Efron, Ashley Tisdale and Vanessa Hudgens will be back.
President of the Disney Channel Rich Ross said: "Are we going to have all the cast back? Probably not... Will we have some of them? I hope so."
He added that it's "likely" HSM 4 will be a TV movie and NOT a cinema release.
High School Musical became a huge hit all over the world after it was first shown on TV in America in 2006.
More than 100 million people in more than 100 countries have seen the film, which tells the story of two pupils who fall in love while auditioning for a play.
Last summer, the second movie smashed cable TV records when 18.6m people in America tuned in to watch its premiere.
Filming on HSM 3 is due to begin at a school in Utah, America, later this month, with the finished film expected to hit cinemas in October.