Katy Perry to Release Feature-Length Special on YouTube Red

The behind-the-scenes special about the singer's four-day Witness World Wide live stream will premiere Oct. 4.

A full-length, behind-the-scenes special about Katy Perry's four-day Witness World Wide livestream will premiere via streaming subscription service YouTube Red on Oct. 4. The singer released a trailer Wednesday (Sept. 27).

The film is called Will You Be My Witness? and gives a look at the creation of the project, as well as the aftermath of Perry being on-camera 24 hours a day, from June 8-12.

The preview shows highlights from the live stream, including appearances by celebrity guests including Anna Kendrick, SiaRuPaul, Caitlyn Jenner and America Ferrera.

"The reason I called this album Witness is everyone in the world is a witness," Perry says in the clip. "We are all observing life, whether we are actively participating or we're just at home observing. We are all a part of this world. I hope by being a part of Witness World Wide, I'll provoke you to be an active witness."

Watch the Will You Be My Witness? trailer below.