WWE's The Last Ride peels back the curtain on the mystique of the Undertaker, giving us insight into the real Mark Calaway. Undertaker is a living legend, but as the first episode of the documentary, "The Greatest Fear," illustrated, getting older started putting doubt into his mind about what he could still bring to the business.

It stirred debate on whether or not Undertaker should retire, which Edge spoke about, mentioning that the decision rests solely with the wrestler. Some also speculated Vince McMahon doesn't want to let the fighter rest in peace and ride off into the sunset. But as the second episode, "The Redemption," reveals, there's a lot we don't know about why McMahon considers Undertaker his favorite superstar, though it does provide some explanation for why he won't make this retirement decision for someone who's more than just a worker to him.

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Throughout the docuseries so far, there are many earnest moments with the duo backstage. The Last Ride has Vince patting Undertaker on the back in the early WrestleMania days, and even checking up on him when he's recovering in his old age. They always connect, hug and shed tears after adding one more event to their resumes. There's a real warmth there.

When Vince's son, Shane, speaks about Undertaker, he makes it clear he's part of the family and feels like Vince's son. And the thought of him retiring actually brought Shane to tears, because it's just so hard to watch someone he grew up idolizing bowing out. More so, Shane knows it will rock his dad's world, because Vince and Undertaker have been through so much. Sure, Triple H, the Rock and Steve Austin have been loyal guys, but the gold standard is Undertaker.

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A big part of that is the WCW. When guys like Bret Hart, Kevin Nash, Scott Hall, Hulk Hogan and Randy Savage left, the Dead Man held firm and even cut promos letting everyone know he was loyal to the then-WWF. Apparently, that vibe was strong backstage, because no amount of money or creative control could prise him away, and it's why he's seen advising Vince as well on certain issues when he's not fighting. Also, when they visited the troops in the Middle East, there's a bond that feels brotherly at times and then at others, as Undertaker says, like a father-son relationship too. His wife, Michelle McCool, admits as much, and she and Undertaker say the same thing: the Phenom would take a bullet for Vince; they transcend the typical employer-employee relationship. It's also why the Dead Man named his son Gunner Vincent, after the head honcho.

There's a trust and love there between them, and when Vince is asked what Undertaker means to him and his company, he chokes up and sheds tears. Vince says he can't answer that on camera, producing one of WWE's most shocking moments, because nothing leaves him at a loss for words. The sentiment continues when Undertaker admits in his dark, depressed moments, Vince was there for him and gave him tough love. And the episode reveals Undertaker's done the same, being one of the few who could barge into the office and let his boss know if he did something wrong.

The way the Dead Man is also revered backstage by Roman Reigns and Seth Rollins as well as other younger wrestlers, you can tell they see him as a leader, and it's something he learned from Vince. Other superstars dub him Vince's right-hand man, but it's more than just ignoring WCW; this is a best friend relationship that is more than just loyalty -- Undertaker understands character, the industry and he has a business mind only Vince can relate to. And for this, Vince sees him as a kindred spirit and a rare gem he wants to hold onto as long as the ride permits.

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