By People Staff
July 02, 2009 12:00 AM
Lester Cohen/WireImage

It’s official! Katie Holmes will perform on So You Think You Can Dance in celebration of the FOX show’s 100th episode, airing July 23, in a song and dance tribute to Judy Garland.

While buzz about her appearance began when photos of Holmes clad in dance gear at the CBS studios in L.A. hit the web last month, it wasn’t her first visit to the show. “She absolutely adores dancing as does her daughter,” according to executive producer Nigel Lythgoe, who said Holmes and her daughter Suri, 3, have been visiting the show’s dress rehearsals for a couple of years now.

Recently, Holmes has been rehearsing herself, sometimes until 11:30 p.m. — with breaks to be with Suri, Lythgoe says — on a New York street scene designed for the number, which was lit by famed cinematographer Dion Beebe, with direction and choreography by her friend, Tyce Diorio.

Inspired by Garland’s song “Get Happy” from the 1950s musical Summer Stock, Holmes will wear “the jacket, the little hat,” Lythgoe says. “It’s just an iconic look. And Katie Holmes has got the legs. Wow!”

Proud husband Tom Cruise and Suri were often on hand to support Holmes. “It was great to see the sort of family bond,” Lythgoe says. “It was beautiful to see!”

Adds Lythgoe: “It was the pride in Tom’s eyes, which I liked. I think we all stood around and felt very proud.”

And why not? All the hard work (Holmes got vocal training from American Idol musical director Ricky Minor) was done in the name of charity, as her performance will introduce the public to the Dizzy Feet Foundation, which she co-founded with Lythgoe, Hairspray director Adam Shankman and Dancing with the Stars judge Carrie Ann Inaba. The organization’s mission is to support, improve and increase access to dance education in the United States.

“I think it’s important for children to experience music and dance,” Holmes said in a statement. “Every child should have the opportunity to discover what it is they like and have access to the very best in that pursuit.”

And how would Holmes’s performance rate with the often unforgiving SYTYCD judges? “I think she would wow the judges and she’d certainly wow the public,” Lythgoe says. “And if anybody didn’t pick the phone up and vote for her, I’d be very surprised.” — Jed DrebenLester Cohen/WireImage