As sad as it is that Orphan Black's fifth season will be its last, there's still a silver lining: We're finally going to get the answers to every last burning question that's been plaguing our minds since the very beginning. Each season has added an extra layer of mystery to the complicated world of clones, and the Season 4 finale definitely set the stage for one hell of a last season.

Let's delve into the very best (and strangest) Season 5 theories:

Kira Has Supernatural Abilities

There's something very strange about Kira. She seems to have a sense for things that are yet to happen, especially when it comes to Helena and Sarah. Considering Helena is Sarah's twin and therefore Kira's aunt, this could be explained as some sort of telepathic twin connection passed down to another generation. However, her predictions often go beyond a mere connection to her own family.

Not to mention how fast she healed after being hit by a car in Season 1. These abilities could be part of Neolution's experiment, since she's the child of a clone and potentially the next step in biological engineering. However, if the next theory on the list is correct, then Kira's healing abilities may just have something to do with her father, Cal...

Cal Is P.T. Westmoreland

This theory has been bouncing around for a while now, and it's supported by some pretty convincing arguments. Before he went off-grid, Cal specialized in micro-optics, designing cutting-edge bee replacement drones. At the end of Season 4, Susan revealed that P.T. Westmoreland was responsible for creating Rachel's eye. Could these two micro-optics specialists be the same person?

If Cal is P.T. Westmoreland, then that means that Kira has probably inherited his immortality— which would explain how she healed so fast after being hit by that car. Not only would this mean that Cal is super old, but he probably purposely impregnated Sarah in order to produce Kira. Now that's creepy.

However, there's one big problem with this theory: the . It was announced that Stephen McHattie will be playing P.T. Westmoreland in Orphan Black Season 5. In case you're not familiar with him, Stephen McHattie is 70 years old— which is a hell of a lot older than 35-year-old Michiel Huisman, who plays Cal. Unless there's some supernatural face-swapping going on, Cal and P.T. Westmoreland are most likely not the same person.

Cal Is Secretly Working For Neolution

Even if Cal isn't P.T. Westmoreland, he still might not be entirely trustworthy. There's a possibility that he's not as innocent as he makes out to be. His mysterious tech genius past; his stash of fake IDs; the fact that the very people who were after Sarah and Kira rocked up at his cabin so fast— none of this looks great for Cal. Every clone has their monitor— could Cal be Sarah's?

Adele Is Working For BrightBorn

Orphan Black has a habit of reintroducing characters thought to be long forgotten, and I'm not just talking about those who get "killed off" (I'm looking at you, Delphine!). Sarah's became incredibly suspicious of Felix's long-lost biological sister, Adele, after discovering that BrightBorn owns GeneConnexions, the company who revealed the siblings' genetic match.

While Sarah accepted that her suspicions about Adele were probably a result of jealousy, Adele's innocence was never proven. She may be a bit of a wreck, but Adele still hasn't shown herself entirely trustworthy.

The Island Is Populated By Monsters

Each season of Orphan Black seems to have an increasing amount of strange science and even supernatural elements, and judging from the sneak peek of Season 5 that was just released, things are about to take a turn for the horrific.

The similarities between Orphan Black's mysterious island and The Island of Dr. Moreau are undeniable— even Susan herself made comparisons. But while obvious parallels between creating clones and the science experiments of H. G. Wells' original novel are obvious, their likeness may be more literal than first thought.

Just check out the mysterious figure Sarah's about to encounter in Season 5:

Running on all fours; making guttural noises; literally acting like an animal; this thing sounds exactly like one of Dr. Moreau's creations. Could this mean that P. T. Westmoreland has been making his own colony of animal-human hybrids?

M.K. Is Hacking Rachel's Eye

Every good sci-fi needs its own computer whiz, and M.K. is just the hacker the Sestras need. But could her technological abilities be intervening in more than we realize?

We know that P. T. Westmoreland created Rachel's eye, and a partnership between the two is now imminent, with Rachel now heading Neolution. But could M.K. have been hacking Rachel's eye in order to reveal the truth to her? Rachel was experiencing "glitches" that turned out to be visions of the Messenger for a while. What could M.K. have to gain from bringing these two together?

Then again, perhaps M.K. has hacked Rachel's eye to use as a camera in order to spy on her. This would definitely make sense, as it would help give the clones an insight into Neolution's plans.

What are your Orphan Black Season 5 theories?