Season 4 of Orphan Black wraps up this week and we’re anxious to see how the finale will manage to go even harder than last week’s episode. Rachel went face to face with Evie Cho over who has a more severe bob, and managed to out-villain Ms. Cho with embarrassing ease. So Brightborn is done, and Rachel’s back on top with Neolution, but lacks allies. Helena’s back, more badass and more pregnant then ever. Delphine’s also back, and possibly hanging out on the very same mysterious island as Cosima. Meanwhile, Cosima and Susan Duncan are debating ethics and drawing closer to a cure for the clone disease.

Co-creator John Fawcett has promised us a “roller coaster”. Here’s the official finale trailer from BBC:

It has some fans worried, after that shot of Sarah with blood on her face, and Cosima swaying at the end, there. We initially thought that Orphan Black was due for a clone death, but now hope is restored, and we believe these two will both survive. The show faced near disaster from fan backlash after almost killing Delphine in the midst of rage about the “Bury Your Gays” trope, and writers would be crazy to kill Cosima now. As for Sarah, her fate may be left in limbo for the season break, but we assume she’ll be back.

Keep in mind, Season 5 will most likely be the last. We’d probably watch a whole season of our favorite clones happily adjusting to new problem-free lives, but that’s not likely to happen, so here are five things we predict will come next.

Delphine and Cosima will be reunited…

…but it won’t be an entirely happy moment. We don’t yet know what’s up with the camp of men loitering on the island in secret, but they’ll surely be major players in Season 5. We’re pretty sure they’re anti-Neolution, which still doesn’t tell us if they will be Clone Club allies or not. The images of the beheaded swan indicate they are specifically targeting the head of LEDA, Susan Duncan. We’re betting they will make their move on Duncan’s lab, and that Delphine has no idea that Cosima is there. Things look ominous for Cosima and Charlotte in the trailer and this preview image, but no matter what these men are after, at least the clones have a strong ally in Delphine. Cosima will be safe for now, but if anything happens to Duncan it will once again imperil the last hope for a cure.

CASTOR will make a reappearance

Remember how the whole Kendall Malone thing started because CASTOR stole Ethan Duncan’s key to the clones’ genetic codes? We think that’s going to come into play again in season five, especially if something happens to Susan Duncan. Way back before the season started, actor Ari Millen teased that there would be more clones. He might have just meant MK, but we could be in to meet another CASTOR brother. At the very least, we expect to see Mark again.

Cal will show up

We haven’t had the slightest hint of Cal all season, but creator Graeme Mason promised he would be back in an “explosive” way, and reconnect with Sarah romantically. No nick-of-time reappearance could match Helena’s epic rescue of Allison, and it’s hard to imagine much time for romance. Hopefully he will be busting back in time to rescue Kira and whisk her off for another period of blessed stability (seriously, when was the last time that girl went to school?), with somehow just enough time for a hot steamy minute with Sarah in the middle. Of course, we have no idea what Cal has been up to all this time, but recall that he had some seedy past military links, so his return could be come in connection with CASTOR. But really, #SaveKira.

Rachel’s coup will hit speedbumps

We know that horny weirdo Ferdinand, the only person who really likes Rachel, is back. His devotion to her seems genuine, but otherwise we can’t imagine she has many friends left. (Also, recall that even Ferdinand hates Neolution, so he may not support her power trip). We see her and Evie face to face at table again in the trailer, and although Rachel looks to be more in control, sister burns bridges like no other. Whatever direction Neolution takes, it will likely continue to be a big factor in season five, so pay close attention to how this negotiation goes down. It will likely result in further division of the Neolution camp and new enemies for LEDA.

Helena will give birth

Orphan Black’s most lethal and also goofiest sestra finally came back last week. We found out she had indeed being laying low, holed up in a yurt in the forest. We’re betting the show will take a page from the Shondaland Guide to Stakes Raising with an ill-timed labor. But all will be well (for a moment) for Helena and her twins. Orphan Black likes to end its seasons with a sentimental moment reaffirming family bonds, and this season has had tension between the clones and their families like no other. What better than all the sisters coming together to greet Helena’s little science babies?

The episode will air Thursday at 10 p.m. on BBC America.

Photos via Tumblr, Blastr