Stranger Things season 4 wraps up on Netflix with today’s release of the season’s final episodes. The show is so popular, in fact, that Netflix crashed early this morning (July 1) due to the high number of people trying to watch the final two episodes.

As it turns out, Metallica’s “Master of Puppets” appears in the season finale. The character Eddie Munson, of course, is a huge heavy music fan on the show. The actor who portrays Munson, Joe Quinn, has even said he immersed himself in metal to get ready for the role and is a true Metallica fan. Fans have been talking about the mysterious guitar solo he played in the trailer for the finale, and now, we can fully witness it.

In the season finale, Metallica’s “Master of Puppets” plays during a critical part of the episode. Reddit’s been having a field day with the scene.

“Yup, ‘Master of Puppets’ is indeed in the season finale. But my god, was it used brilliantly. I’ve been waiting for this show to really use Metallica and not just kinda have it in the background,” a Metallica fan said on Reddit. “You can’t have a piece of entertainment that’s set in an ’80s time-frame and not play Metallica. They definitely did the song justice. Big congrats to Metallica! I’m 100 percent certain ‘MoP’ is gonna have a massive resurgence.”

The soundtrack for the season offers a heavy dose of rock and metal, including songs from Metallica, KISS, Talking Heads, Journey with Steve Perry, The Beach Boys and more.

Check out Metallica’s “Master of Puppets” featured in the Stranger Things’ season four finale below, but note that there’s a big spoiler!

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