Stranger Things' second season is going to be even strangerer!

Netflix's hit debuted its second trailer at San Diego Comic-Con today, to the delight of the supernatural series' adoring fans, who packed the massive Hall H to watch their world turn upside down. With cast and crew in attendance, the extended glimpse at the series may not have revealed everything about the secretive sequel; but it did open the doors wide enough for a demogorgon to sneak on through.

To get you up to speed, the surprise hit focuses on the small town of Hawkins, Indiana, which is terrorized by a mysterious creature from an alternate reality the town's kids call the Upside Down. A young girl with psychic powers named Eleven (Millie Bobby Brown) has a connection to the Upside Down — and the creature — and together with four boys, they search for their missing friend. Along the way, they lose one of their own (#RIPBarb), before finally bringing things back to normal.

...Or did they? With the returned Will Byers (Noah Schnapp) burping up slugs like he's a 1980's Ron Weasley, Chief Hopper (David Harbour) working for the enemy, and an enormous monster bursting out of lightning filled red skies, it seems like Stranger Things 2 is about to turn things up to — wait for it — eleven.

The trailer kicks off with the boys playing classic, impossible video game "Dragon's Lair." They're all having fun when Will blips into the Upside Down. There, he glimpses the enormous monster we've seen previously in trailers. And then it kicks into Michael Jackson's "Thriller" over scenes of the gang on Halloween. Dressed as Ghostbusters, they open up a ghost trap. There's hints the Upside Down is spreading. "Will, wake up!" yells Joyce, as tendrils of darkness chase Will down a school hallway. And then: she's back! Eleven pushes her way out of a hole in the upside down, into the school. Trailer over!

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Stranger Things 2 is created by Matt & Ross Duffer, and stars Millie Bobby Brown, Gaten Matarazzo, Caleb McLaughlin, Noah Schnapp, Finn Wolfhard, David Harbour, Winona Ryder, Natalia Dyer, Charlie Heaton, and Joe Keery. Sean Astin and Paul Reiser join the cast for Season 2.

Stranger Things returns for Season 2 on Friday, Oct. 27 on Netflix.

With reporting by Tim Surette.