According to Walt Disney Studios Motion Picture Productions, all cast from “High School Musical” already signed for the big screen release and final installment, “High School Musical 3: Senior Year.”

Zac Efron, Vanessa Hudgens, Ashley Tisdale, Lucas Grabeel, Corbin Bleu and Monique Coleman returned to film “HSM 3” after the first two movies recorded a big number of viewers when they were aired on the Disney Channel.

The movie will start shooting in the spring and will be released October 24, the Hollywood Reporter informs.

According to People, director Kenny Ortega feels happy to be able to work again with the cast, a couple of young actors who were unknown before the first HSM movie was launched in 2006.

Ortega says: “I am the luckiest guy in the world and I know it. This will be our last time together and I love working with these kids so much. It's going to be great."

"High School Musical" was launched on the Disney Channel on January 2006 and became an instant hit. In August its sequel was launched attracting the biggest audience ever for a cable telecast having a rating of 18.6 million viewers.

The screenplay for HSM 3 is written by Peter Barsocchini and is produced by Bill Borden, Barry Rosenbush and Don Schain.

This time the third HSM shows Troy (Efron) and Gabriella (Hudgens) to be facing some trouble in their relation as they might separate as they head off to different colleges.

Along with the other Wildcats, they will plan a musical that will reflect their experiences, hopes and fears regarding their future.

There were doubts that Disney will close the deal with the cast since the actors were starting to ask for more money as they became instant superstars from unknown actors.

According to Disney Channel the first HSM had 250 million viewers since its debut in 2006.