Hello, sestras, and welcome back to our weekly recaps of BBC America’s Orphan Black. If you’ve not seen the season four finale episode, “From Dancing Mice to Psychopaths,” note that there will be insanely major spoilers below. You’ve been warned! 

With several mysteries solved, a bunch of crazy science deduced, and more than a handful of insane reveals and scary set-ups, Orphan Black really did a number on us in its season four finale. The feels! The worries! The anxiety! The science fiction horrorshow of it all! But oh, what a way to set up the show’s upcoming fifth and final season, eh? And I mean, to have Delphine alive and reunited with Cosima? It’s the cherry atop this Neolution-whipped sundae.

After the brutally beautiful opening—Cosima and Susan Duncan have figured out a cure! She and Charlotte will hopefully be well again!—the need for scientific control quickly took hold of the story. And everyone wants a seat at the table: Evie Cho demanded to be kept (R.I.P. Evie Cho, killed by your own science, so poetic); Susan decided it was time to restart human cloning; Cosima wanted to simply be cured and maybe-possibly stop the whole resurgence of clones thing from happening, and Sarah wanted to protect Cosima, her sisters, Mrs. S and Kira, and the science that, arguably, allows them their freedom. It was a lot to pack into one episode …and that doesn’t even take into consideration the superNeo revelation.

And then there was Rachel and the board, who decided the best course of action was to simply combine the two warring sciences: implant maggotbots inside human clones and finally kickstart the next step of the human evolutionary process. It’s interesting that Rachel is so hungry to control the “lab rats”, which the science that legally owns her likely also considers her. But that’s the conflicted beauty of Rachel: she wants for herself what she hopes to remove from her sisters—personhood. (Funny how that works and is totally analogous to what’s going on in the political systems of the world when it comes to women!) To be considered a miracle of science isn’t enough, she must also run the whole operation and restart the program that created her, even though doing so makes her, effectively, not a person at all. Her ruthlessness is worse than Evie Cho’s, and we’re sure this will mean Rachel’s death next season. Never forget this tone-deafly bellowed line from tonight: “If we want to know if our lab rats’ tails will grow back, we damn well will cut them off and see!”

The action quickly moved back to the cloney island of Doctor Moreau, though, with Rachel returning (sans Ira! Who almost won line of the night with his “he has his socks on” quip about Ferdinand) to retrieve the science and ended up seriously messing up Susan Duncan and Sarah in the process. (Will Sarah survive?! Are Mrs. S and Kira going to be OK?! Why is Ferdinand the creepyworst? AHHHHH so many questions.) Thankfully, Charlotte and Cosima went on an adventure of their own to the ultra-mysterious other side of the island from whence Rachel’s visions came. It’s also where Ian Van Lier—which: could that name be any more of a red flag?—sent Delphine to recover from her injuries, and where the mysterious Messenger (Geza Kovac) lives with (wait for it/we can only assume) P.T. Westmoreland. Yeah, that’s right: the dude who wrote the literal book on Neolution over 100 years ago is somehow still alive. And apparently he’s a pretty intimidating figure if Delphine’s all “yo maybe say literally nothing about anything, especially the cells you brought here.” Now that’s some crazy-ass science, man.

So that’s where season five will take us: deep into the two warring factions of Neolution, where Rachel will lie her pretty little messed up head. Serious question: do we think P.T. Westmoreland will look like Cassandra from Doctor Who?

How we learned about these factions was, perhaps, the highlight of the night, though. Yes, of course we’re talkin’ Krystal! Everyone’s favorite sleuth—who saw Van Lier take Delphine away—clued Sarah and Felix and Art into what was going on since they were just so out of the loop it was, like, adorable. (Also: Krystal is the best.) Only Krystal the sage, Krystal the wise, Krystal the deeply embedded, has uncovered that the heart of all of this revolves around human experiments being controlled by two factions of the same industry. For her, it’s Estee Lauder and a Swedish company named Neolution—and honestly if Estee Lauder also comes into play, I’ll lose my gourd.

We also—finally!—got another cloneswap after an entire season without them. In perfect moment, Sarah-as-Krystal bum-rushed Van Lier with a litany of hilariously on-point questions and comments in order to get the word out to the other journalists about Neolution and their cause: “Are you a Neolutionist?” “I’m TMZ.” “Do I look stupid?” “No photos.”

How this plays into where the sestras will land at the end of next season is truly a mystery. Will Castor come into play (I’m still not letting go of this whole Krystal-had-a-Castor-notebook thing)? What happened to Mark and Gracie and her Helena-babies? And while we’re at it: Tony? Will Sarah survive the island? What about Cosima? How does any of this play into Donnie’s trial? Will Susan Duncan end up on top of Neolution again? Does P.T. Westmoreland really want human clones again? Will Adele come back (we’re sure she will)? How about Cal? And who the heck is this Messenger guy, really?

We got little clues as to motivations for some people—Rachel did call Neolution “a means to an end,” which leads us to believe that maybe she’s not such a big believer in the religious aspect of it all, erring more on the side of “that Leekie pop-futurism.” But is that what Westmoreland wants? And what’s the best option for all our clone sestras? The mystery continues!

Watch the cast talk the breakneck mystery of season four:

What did you think of the season four finale? Looking forward to the next? Let us know in the comments below!

Images: BBC America

Alicia Lutes is the managing editor of Nerdist, co-host of Fangirling, and president of our in-office Clone Club chapter. Find her on Twitter—if you’re into that sort of thing.