It's long been suggested by fans that the Friday the 13th franchise shares the same universe as the Evil Dead movies. Specifically, the explanation for Jason's inability to be killed and supernatural power come from him being what's referred to as a Deadite in Evil Dead. This is now more than a theory, as Jason Goes to Hell director Adam Marcus has officially confirmed that Jason's mom used the Necronomicon, aka the Book of the Dead, to bring back her son. Here's what he had to say about it in a recent interview.

"(I) wanted to create a mythology for Jason in this movie, because it had driven me nuts as a viewer. She (Pamela Voorhees) makes a deal with the devil by reading from the Necronomicon to bring back her son. This is why Jason isn't Jason. He's Jason plus The Evil Dead, and now I can believe that he can go from a little boy that lives in a lake, to a full grown man in a couple of months, to Zombie Jason, to never being able to kill this guy. That, to me, is way more interesting as a mashup, and (Sam) Raimi loved it!"

Not only does the director of what, at the time, was the "final" Friday the 13th movie sign off on this, but Sam Raimi, the man who directed Evil Dead, also gives it the thumbs up. That's a huge deal. It explains a lot about the mythology of the Friday the 13th universe and it also explains why the Necronomicon appears in the Voorhees' basement in Jason Goes to Hell. Adam Marcus had to be sneaky about it, but he goes so far as to say that this is "absolutely canon."

"It's not like I could tell New Line my plan to include The Evil Dead, because they don't own The Evil Dead. So it had to be an Easter egg, and I did focus on it...there's a whole scene that includes the book, and I hoped people would get it and could figure out that's what I'm up to. So yes, in my opinion, Jason Voorhees is a Deadite. He's one of The Evil Dead. It absolutely is canon."

Jason Goes to Hell teased a fight between Jason and Freddy Kreuger that would eventually happen in Freddy vs. Jason. However, there were plans for Freddy vs. Jason vs. Ash that never materialized, which now make even more sense. As Bruce Campbell explained last year, they wouldn't have had enough creative control to justify doing the crossover.

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"I'll be honest with you. I'm not real interested in cross overs. One of the main reasons why Ash vs. Jason vs. Freddy did not come to pass is because we couldn't control any other character other than Ash. That felt like a creatively bankrupt way to go. Not to mention, you're splitting the proceeds three ways with partners you might not want."

Friday the 13th is in a precarious place right now. The 2009 reboot didn't do what the studio wanted and it's been impossible to get a sequel going ever since. And considering that the last movie was saw was a reboot, the old canon is simply that. Old. But still, this new information from Adam Marcus, via Horror Geek Life, provides fans with confirmation of something they've long believed. So even if the eventual new Friday the 13th canon ignores this Evil Dead link, it definitely exists.