Seven-time Grammy winner Gladys Knight stars in the film as Wilma, a church elder determined to rescue and inspire a struggling nightclub singer, April, played by Taraji P. Henson.
Knight, although nervous when she got the call from Perry, admitted she always wanted to grow in the acting arena and called her experience "the most amazing event and journey" on "The Early Show" Wednesday. Knight performed two songs from the film on the show.
The music icon also paid tribute to the late Michael Jackson at his private burial service by singing, "His Eye Is On The Sparrow" and "The Lord's Prayer."
"I thought that would be in my heart, a message Michael would want to portray, knowing him as I did, to let everybody know, you know, I'm fine. Because he had that ... love. That's what he was all about. And that's what most people didn't understand about him anyway," Knight said.
Knight is also preparing for her "Farewell Tour," which begins in October in London.
To hear more about how the Jackson family is coping and to listen to Knight's performance, cick the play button below:
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