Katie Holmes Katie Holmes

Apparently, Katie Holmes does think she can dance — and like Judy Garland, no less.

Holmes, who was spotted rehearsing earlier this week at the So You Think You Can Dance soundstage, will show off her fancy footwork on the Fox series in a tribute to Garland's 1950 musical Summer Stock, Us Weekly reports. And not unlike her song-and-dance appearance on Eli Stone last season, Holmes will also sing Garland's "Get Happy" from the film, the magazine says.

For the routine, a witness tells Us that Holmes will don an all-black outfit, including a velvet fedora, patent-leather heels, and nylon stockings. Eight male dancers will kick up their heels alongside the actress in matching suits and ties. The number ends in a flourish with Holmes tossing her fedora in the air for one of the men to catch.

"[Holmes] is killing it," a source tells Us."She looks incredible. She is just doing an amazing job. Everyone is absolutely floored by how talented she is."

A custom set was made for the production, which gives the illusion that Holmes is performing on a rooftop against a sky backdrop, acccording to the witness.

The routine is choreographed by Tyce Diorio and directed by Dance executive producer/judge Nigel Lythgoe, who previously dismissed Holmes' reported drop-by to Us as "just a rumor for now."

Holmes' performance was originally scheduled to air July 8 to mark Dance's milestone 100th episode, but it may air this week due to leaks, the source tells Us.

Neither Fox nor Lythgoe have confirmed Holmes' appearance.

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