Disney will premiere "High School Musical 4" on the Disney Channel in 2010, continuing the franchise that, according to Nielsen SoundScan, has sold 9.5 million soundtrack copies to date.

While the script is still being written, a Disney Channel spokesperson says they don't anticipate the return of any of the "HSM" stars at this point. In addition, long-time producer, director and choreographer Kenny Ortega will not be part of "HSM 4."

The TV movie will begin production later this year, and will focus on a "love triangle set against the crosstown school rivalry between the East High Wildcats and the West High Knights." Peter Barsocchini, who wrote the previous "HSM" properties, returns as the screenwriter, while Bill Borden and Barry Rosenbush remain part of the production team.

"The 'High School Musical' trilogy introduced a new generation to the celebrated genre of movie musicals," says Gary Marsh, president, Entertainment, Disney Channels Worldwide. "In crafting this next iteration, we've challenged the entire creative team to raise the bar again—and create something truly worthy of this extraordinary global phenomenon."

The first two itierations of "HSM" debuted on the Disney Channel. The first "HSM" debuted in January 2006; since then, Disney estimates its been seen by 290 million viewers worldwide. "HSM 2" premiered in August 2007; Disney estimates its total audience is now 300 million.

"High School Musical 3: Senior Year" was the first in the series to get a
release in movie theaters; to date, it has earned $250 million at the global box office.