As seen above, USA Today has released a special preview clip for Sunday's episode.
Chapter 4 will focus on Taker's disappointing match with WWE Hall of Famer Bill Goldberg at WWE Super ShowDown last year, and how the man behind the gimmick was forced to make a "major decision" about his future as The Undertaker, which will be revealed on the show.
Chapter 4 will also look at Taker's dedication to his character. Per USA Today, WWE Hall of Famer Mick Foley appears on the episode and discusses Mark Calaway's persistent presence as The Undertaker being so strong that he doesn't even refer to his longtime colleague by his real name.
"We all treat that character with such reverence. I don't even call him Mark anymore. I haven't called him Mark in 20 years. I'd say it's safe to say I know less about him as a human being now than I did 28 years ago, and I like it that way," Foley said.
Taker recently told CBS Sports that the last episode of the docuseries has yet to be filmed and taping is ongoing. The fifth and final chapter is scheduled to premiere on Sunday, June 21 at 10am ET via on demand.