Oprah fills the audience with 300 students.

For the show A Global Adventure: The O Ambassadors Launch, Oprah fills the audience with more than 300 students.

Oprah poses with a group of students after announcing the launch O Ambassadors, one of her most ambitious projects to date.

A guest named Marcy asks Dr. Oz a question during the show Dr. Oz Investigates the Man Who Turned Blue.

The Oprah Show stage has been transformed into a Dancing with the Stars ballroom for the show Oprah Presents Dancing with the Stars Champions. During a dress rehearsal, race car driver Helio Castroneves and his dancing partner, Julianne Hough, talk to crew members.

Minutes before the Dancing with the Stars champions perform, Oprah introduces the show.

Soap star Kelly Monaco, the only female Dancing with the Stars champion, and her partner, Alec Mazo, await their cue to take the stage.

The camera rolls on NFL star Emmitt Smith and his partner, Cheryl Burke, as they get ready to begin their dance to "Que Bueno Baila Usted."

Dancing with the Stars pro Derek Hough surprised Deneen—a huge fan of the series—with the chance to show off her ballroom moves on Oprah. She is all smiles after their performance!

Backstage after Lisa Ling Investigates the Hidden World of Puppy Mills, which she dedicated to her late cocker spaniel Sophie, Oprah poses with Shrimp, a puppy rescued by animal activist Bill Smith.

Oprah chats with show guests Michael, Anita and Carson Kressley during a break in the show How to Look Good Naked.

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