The Undertaker defeated AJ Styles in a “Boneyard Match” at WrestleMania 36, participating in one of the highlights of the event. Nearly thirty years after making his WWE debut, the legendary wrestler continues to be featured prominently in some of the company’s biggest shows.

A few years ago, it appeared unlikely that The Undertaker would still be wrestling in 2020. The Deadman seemingly retired in 2017 after he was pinned by Roman Reigns in the main event WrestleMania 33 and left his gear in the ring.

The Undertaker showed back up at WrestleMania 34, where he squashed John Cena. He’s had close to 10 matches since then and it’s unknown when the 55-year-old will walk away from the business.

“I want them thinking, ‘This guy’s got a lot left in the tank,’” The Undertaker said in a trailer for WWE’s new limited series. “If I can leave with that, I’ll be content. I can walk away. I say that, but I’ve been saying it for a long time.”

“Undertaker: The Last Ride” premieres Sunday night at approximately 10 p.m. EDT on the WWE Network after the Money in the Bank pay-per-view. It’ll be the first episode of a five-part series, giving a closer look at The Undertaker as he heads toward the end of his career.

“You start to hear things. People talking, ‘He’s too old. He shouldn’t do this. He shouldn’t do that.’ Well, that’s up for me to decide,” The Undertaker said.

According to wwe.com, Sunday’s episode will detail The Undertaker’s preparation for his match with Reigns three years ago. It will also look back at the aftermath of WrestleMania 30, which saw the Phenom’s legendary Streak come to an end with a loss to Brock Lesnar.

Even after he stopped wrestling full time in 2010, The Undertaker was still putting on great matches. His matches with Triple H at WrestleMania 27 and WrestleMania 28 were among the best each year. The Undertaker and CM Punk stole the show at WrestleMania 29.

The Undertaker suffered a concussion against Lesnar at WrestleMania 30, and he still has no recollection of the match. After defeating Bray Wyatt at WrestleMania 31, The Undertaker continued his feud with Lesnar at Summerslam and Hell in a Cell in 2015.

The Undertaker defeated Shane McMahon at WrestleMania 32 before facing Reigns a year later. Maybe Sunday’s episode will provide more answers regarding why the WWE superstar has continued to put off retirement.

“For the last few years, I’ve had this internal struggle of I don’t want to stay too long and become a parity of myself,” The Undertaker says in “The Last Ride.”

“I’m either gonna go out with a match that’s fitting The Undertaker at WrestleMania or I’m going out on my shield, one way or another.”

A new episode of “The Last Ride” will air on the WWE Network on May 10, May 17 and May 24. The final two parts are set to premiere on June 14 and June 21.

The Undertaker
The Undertaker recovers during his fight against Brock Lesner at the WWE SummerSlam 2015 at Barclays Center of Brooklyn in New York City, Aug. 23, 2015. JP Yim/Getty Images