The latest Stranger Things season 4 trailer shows a grandfather clock within the mysterious Creel House shattering, leading to a number of theories as to what the shot could mean. Clocks have featured prominently in the earlier Stranger Things season 4 promos as well, and put all together, the footage that’s been released has some interesting implications. Though Stranger Things season 4 doesn’t release on Netflix until 2022, the streamer has revealed just enough to keep speculation high until then.

Because of the way Stranger Things season 3 ended and the substantial amount of time that’s passed since, season 4 may be rather different than what viewers have come to expect from the series. Hopper is imprisoned in Russia at the start of the season – though he’s presumed dead by everyone in Hawkins – Eleven, Joyce, and Will Byers are moved away, and the whole crew has grown older. The Upside Down portal appeared to be closed for good at the end of Stranger Things season 3, but it seems that the monsters are returning through some new method.

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Due to its prevalence and placement in the promo footage, some have theorized that the Creel House clock will play a role in that return to the Upside Down in Stranger Things season 4 – a belief that’s only been magnified by the clock’s mysterious shattering. The haunted house has a grotesque backstory that will surely tie into the show’s preexisting supernatural lore, and there are even hints that the clock could be connected to Eleven, specifically.

Theory: The Stranger Things Clock Is An Upside Down Gate

Stranger Things season 4 Creel House clock

The third Stranger Things season 4 trailer focuses on the Creel House – a new location with a dark and mysterious past. As it’s been understood so far, the Creel House was the site of a gruesome series of murders committed by Victor Creel (Nightmare on Elm Street’s Robert Englun). The promo material for Stranger Things season 4 suggests that Creel was overtaken or compelled by some sort of dark spirit. In the world of the show, that basically guarantees a connection to the Upside Down.

If the Creel House is tied to the Upside Down, it’s possible that the clock serves as some kind of gate. The teaser trailer ends with the clock’s glass breaking and a flash of the Upside Down version of the room. It’s a all still speculation right now, but one theory says that the breaking glass represents whatever portal once opened up in the Creel House reopening. In other words, the clock acts as a doorway to the Upside Down in Stranger Things season 4 – one that opened years ago when Victor Creel murdered his family, and which may be opening again in the present-day timeline of the show.

Theory: Eleven Breaks The Creel House Clock

Millie Bobby Brown as Eleven and grandfather clock in Stranger Things

Another theory concerning the broken clock in the Stranger Things season 4 teaser trailer is that it’s broken by Eleven. In an earlier teaser, Matthew Modine’s Dr. Martin Brenner character is shown walking through the halls of Hawkins Lab prior to the events of Stranger Things season 1. Children are shown honing their psychic abilities, and Eleven’s room is seen from the outside. At the end of the trailer, Dr. Brenner tells the children that he has something special planned for them.

Related: Stranger Things Season 4 Trailer: Every Reveal

It’s unclear when exactly in the Stranger Things timeline this trailer takes place, but it’s presumably pretty close to the start of the show. In that teaser, a different clock is shown in Hawkins Lab, which reads just before three o’clock. That’s the exact same time seen on the Creel House clock when it explodes, suggesting that the shot of the glass breaking could happen at the exact same moment as the Hawkins Lab scene.

What exactly does that mean? Nothing explicitly, but if both scenes actually take place at the same time, it could be that Stranger Things season 4’s Creel House clock is connected to Eleven somehow. Maybe she’s the one who breaks the glass. Maybe the clock scene happens when Eleven first escapes Hawkins Lab. That would make the house a key part of the connection between Hawkins and the Upside Down, which could explain why Dustin, Lucas, Steve and Max go there in the first place.

Theory: Stranger Things 4 Will Involve Time Travel

Stranger Things theory season 4 will be about time travel

The last big theory about the Stranger Things season 4 clock exploding is that it’s a symbol of a new direction for the series – time travel. The show has already distorted real-world space-time by introducing the Upside Down, which makes time travel a distinct possibility. The Creel House murders took place long before Stranger Things season 1, which makes the past more important than ever in season 4.

One way Stranger Things season 4 could feature time travel is by revealing new details about the nature of the Upside Down. Perhaps the dark realm isn’t just a parallel universe, but a way to reach between different eras of the real world as well. Maybe Eleven’s opening of the Upside Down in Stranger Things season 1 somehow reached back in time through the other dimension to crack open a portal in Hawkins in the past, causing the tragedy in the Creel House from the future. It may sound like a stretch, but it’s the exact kind of high-concept sci-fi story Stranger Things excels at.

Another theory, which has existed in the Stranger Things fandom for some time, is that the Upside Down is actually a future version of Earth. Because the series is set during the Cold War, the nuclear arms race is a prevalent background theme, and it will continue to be one with Hopper being imprisoned in Russia in season 4. Maybe Stranger Things takes place in a universe where the Earth falls to nuclear war, leading to an uninhabitable wasteland that becomes the Upside Down. That would explain the radiation in the Upside Down, and it would open up a lot more time travel story possibilities. For now, it’s impossible to say what the broken clock in Stranger Things season 4 means, but there are a lot of exciting possibilities for what’s to come.

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