The teaser trailers for Stranger Things season 4 have featured clocks in prominent and curious ways, sparking theories as to what they could mean for the Netflix series. The new season has teased some big changes, with numerous characters having left Hawkins, a substantial amount of time having passed, and new mysteries of the Upside Down waiting to be revealed. Netflix hasn’t revealed too much concrete about the story of Stranger Things season 4 yet, but the conspicuous clocks in the promo footage tease some exciting possibilities.

Several major storylines were wrapped up at the end of Stranger Things season 3, but others had just begun. The Hawkins portal to the Upside Down was closed, a powerless Eleven left Hawkins with Joyce and Will Byers, and Jim Hopper – presumed dead – was imprisoned in Siberia. It would make sense for Stranger Things season 4 to focus on the discovery and rescue of Hopper and Eleven’s quest to regain her powers, but the teaser trailers have also pointed to some new mysterious and horrors lying in wait in Hawkins itself.

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How will Eleven, Hopper, Mike, and the rest of the gang all come back together in Stranger Things season 4, with its haunted house? Some theories say it all has to do with the clocks that have featured so prominently in the show’s recent promotional footage. No official release date has been announced yet for season 4, and until it comes out in 2022, speculation will continue. Here are the biggest clock theories for Stranger Things season 4.

Stranger Things 4’s Clock Is Tied To Eleven Theory

Millie Bobby Brown as Eleven and grandfather clock in Stranger Things

The second teaser trailer for Stranger Things season 4 showed a glimpse of Hawkins Lab prior to the events of season 1. Different children are honing their psychic abilities on toys and games, and Matthew Modine’s Dr. Martin Brenner character is heard addressing them, declaring that he has something special planned. A room with the number eleven is shown at the end, but the trailer begins with a close-up shot of a clock reading almost 3:00. In the third teaser trailer for Stranger Things season 4, the grandfather clock in the Creel House reads the exact same time when it shatters.

That curious connection between the clocks suggests a particular significance for Eleven. In the Creel House teaser, the clock shatters sometime after the murders in the house took place, as the windows are clearly boarded up. That could mean that something that happened at Hawkins Lab triggered an event within the Creel House clock – likely something to do with the Upside Down. Could the Hawkins Lab trigger have been caused by Eleven specifically? Given her immense power, it’s certainly possible. However, the idea of a connection between the lab and the Creel House itself poses another theory.

Stranger Things 4’s Clock Is An Upside Down Gate Theory

Clock in Stranger Things season 4

Some have theorized that Stranger Things season 4’s Creel House clock could be an early instance of an Upside Down Gate. The story of Victor Creel, the new character being played by Nightmare on Elm Street star Robert Englund, seems to be that he killed his family while possessed by some otherworldly entity and was subsequently institutionalized. In Stranger Things, that means something from the Upside Down, hinting that the strange dimension could be connected to the house somehow. Perhaps the Mind Flayer, or some other similarly monstrous creature, extended itself through a tear tied to the clock to possess Creel and spark his violent rampage.

Related: How Old The Young Cast Of Stranger Things Will Be When Season 4 Finally Airs

If that’s what happened, the connection between the two clocks in the teasers might indicate that Eleven, or another subject at Hawkins Lab, reopened the Creel House tear during their psychic experiments. Eleven was the cause of the initial portal that led to the first Demogorgon’s emergence, but the Stranger Things season 4 trailers could be hinting that she actually opened an earlier tear. Or, maybe the Creel House clock is part of what caused the Stranger Things season 1 portal in the first place.

Stranger Things Season 4 Is Using Time Travel Theory

Stranger Things season 4 teaser supports two theories

Another theory about the clocks in Stranger Things season 4’s trailers is that they’re meant as clues that the show will be dealing with time travel. Given the territory the series has covered previously, that’s not a ridiculous assumption to make. As it’s been explained in the past, the Upside Down is already a major distortion of space-time since it's essentially a parallel universe. That means that Stranger Things already has all the sci-fi foundation necessary to introduce time travel, and the prevalent clocks in the season 4 promos suggest that could be exactly what’s happening.

A time travel storyline in Stranger Things season 4 would also fit with what’s been revealed so far. The Creel House is clearly a big part of the new season, and the murders that took place there would be decades old by the events of Stranger Things season 4. Time travel could play into the rescue of Hopper from Russia, and some have even theorized that it could play a role in Eleven getting her powers back – allowing her to journey back to an earlier time and gain a fuller understanding of her abilities. Stranger Things has gone some truly wild places in its first three seasons on Netflix's streaming service and allowing time travel in season 4 could be just the boost the series needs to keep things interesting. But there’s one more big theory about the clocks in Stranger Things that suggests the show may have already been dealing with time travel since the very beginning of the start of season 1, back in 2016.

Stranger Things’ Upside Down Is The Future Theory

Stranger Things Season 1 Episode 8 Will sees the Upside Down when he goes to the bathroom

For all of the time that Stranger Things has spent there, the Upside Down is still largely unexplained. One theory holds that the terrifying realm is not just a parallel dimension, but rather a future version of Earth spliced together with the era of the show through the portals. The theory claims that the planet experiences some sort of apocalyptic event in the future – possibly nuclear, given the radiation of the Upside Down – and that the ensuing wasteland breeds the deadly monsters seen in Stranger Things.

Related: Stranger Things: The Upside Down Is Future Earth Theory Explained

That theory of the Upside Down would explain why the realm seems to be tied to the clocks in Stranger Things season 4. If the Creel House clock really did play a role in opening the season 1 portal, that idea becomes even more plausible. Stranger Things has always been a Cold War show, and Hopper’s Soviet imprisonment in season 4 is keeping that part of the story in the forefront. With that in mind, it’s possible that the Stranger Things timeline ends with nuclear war, and that the Upside Down is just that future seeping back into the past.

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