JoJo Siwa, Jesse Tyler Ferguson join 'High School Musical: The Musical: The Series' season 3

JoJo Siwa and Jesse Tyler Ferguson are joining "High School Musical: The Musical: The Series."

The pair will appear on the Disney+ series, the third season of which premieres July 27, in guest roles, joining previously announced guest star Corbin Bleu from the "High School Musical" film franchise.

Season 3 of "High School Musical: The Musical: The Series" has the Wildcats at Camp Shallow Lake, a sleepaway camp in California, as they work toward putting on a production of "Frozen." Music from "Camp Rock" and the "High School Musical" movies will also be featured.

Siwa, who recently was runner-up on "Dancing With the Stars" season 30 and is a judge on season 17 of "So You Think You Can Dance," will play Madison, an alum of Camp Shallow Lake. Ferguson, who starred on "Modern Family" and just won a Tony for "Take Me Out" on Broadway, will play Marvin, who is described as an old family friend of Olivia Rodrigo's character, Nini.

Disney+ also dropped the official trailer for season 3, giving fans an extensive look at all the fun to expect as the Wildcats set out to put on yet another show-stopping production.

"High School Musical: The Musical: The Series" stars Joshua Bassett (Ricky), Sofia Wylie (Gina), Matt Cornett (E.J.), Julia Lester (Ashlyn), Dara Reneé (Kourtney), Frankie Rodriguez (Carlos), Saylor Bell Curda (Maddox) and Adrian Lyles (Jet).

Recurring guest stars for season 3, in addition to Siwa and Ferguson, include Bleu (himself), Meg Donnelly (Val), Jason Earles (Dewey Wood), Kate Reinders (Miss Jenn), Aria Brooks (Alex), Liamani Segura (Emmy), Ben Stillwell (Channing) and Rodrigo. Olivia Rose Keegan (Lily), Larry Saperstein (Big Red) and Joe Serafini also guest star.

"High School Musical: The Musical: The Series" season 3 premieres July 27 on Disney+.

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