Like a starship capable of disappearing and reappearing instantly, Star Trek: Discovery is back after a short break. This Sunday, the twisty and thrilling show will return for its mid-season debut, launching the remainder of Season 1, with a chunk of episodes being called “Chapter 2.”

At this point, Discovery is by far the Trek series with the most upsets and twists. Which is saying something, considering only nine episodes have aired. During that time we’ve seen main characters perish, import Klingons vanish, and one Starfleet captain who acts like he’s about to get caught drinking on the job like every other episode. Plus, the last episode of 2017 left us with an interdimensional cliffhanger, which effectively rebooted the whole show. After using the spore drive to supposedly jump the USS Discovery to a safe starbase, the ship has instead ended up, well, nobody knows.

With that in mind, here are five theories to start betting on before Star Trek: Discovery beams back this Sunday.

Speculation follows, so possible spoilers for Star Trek: Discovery are ahead, depending on which universe we’re in.

In the original series, Spock had a little beard in the Mirror Universe.

The Crew Has Jumped to the Mirror Universe

Because it’s pretty obvious Captain Lorca jumped the ship into an unknown dimension on purpose, the leading theory is that we’ve arrived in the famous Mirror Universe. For those who haven’t been following along with the crazy fan theories since Discovery debuted last year, here’s the deal. This theory presupposes Captain Lorca is really from the Mirror Universe — an evil dimension first explored in the original Star Trek — and he’s been trying to get back there. Lots of stuff in the previous season lends credence to this, particularly him not remembering a bunch of stuff he and Cornwell did together when they were younger. So, if Lorca used the spore drive to move the Discovery into his home dimension, it might be the Mirror Universe.

The Crew Has Jumped to a Different Alternate Reality

Or maybe not? Perhaps Lorca is from an alternate reality but not the Mirror Universe. Maybe his dimension is slightly different than the one we’re seeing. True, it has been confirmed that Discovery will visit the Mirror Universe at some point this season. But, based on the conversation Stamets and Lorca had in “Into the Forest I Go,” it’s reasonable to assume the ship and crew could go to more than one alternate universe before this season ends.

Burnham is going to be bummed if he's a Klingon.

Tyler Is Voq the Klingon in Disguise

What’s up with Tyler? Why does he have such a bond with his former Klingon jailer, L’Rell? The good money here is on Tyler being a surgically altered Klingon spy, once known as Voq. The only weird thing about this is simple: Why would L’Rell also erase Voq’s memories of being a Klingon? What’s the long con there? If Tyler isn’t human deep down, at this point, he totally thinks he is. So, if this theory comes true, it will be less about the reveal and more about the motivations.

Stamets Has Merged With Various Versions of Himself From a Bunch of Alternate Universes

In “Choose Your Pain,” we briefly saw an alternate version of Stamets looking back at our dimension from inside of the mirror. Then, in “Into the Forest I Go,” Stamets mentioned he could see “all the permutations,” presumably referring to the various alternate dimensions he may have glimpsed before the ship jumped. So, perhaps he’s now literally all of his alternate selves rolled into one person. This kind of thing has happened on Star Trek before. In the Voyager episode “Relativity,” we learned copies of people from different dimensions can be forcibly integrated with alternate versions of themselves. Does this mean Stamets is now literally every Stamets?

The Whole Show Has Never Been in the Prime Universe But Might Jump There

Here’s a big one. Since Discovery launched, some fans have talked about some of the obvious canonical inconsistencies between the 23rd century of this show and the original series. While most of these “problems” are superficial (uniforms are different, ships are sleeker), it’s somewhat conceivable that the entire show did all of this on purpose. Perhaps Star Trek: Discovery is from a different dimension of Trek than the rest of the canon. But because they have this nifty spore drive that allows for interdimensional travel, it seems possible that the Discovery could discover the original Trek timeline, assuming they’re not already in it.


Star Trek: Discovery debuts Chapter 2 of its first season on January 7 at 8:30 p.m. Eastern on CBS All Access.