Orphan Black wraps up its fourth season tonight, and it’s got us stressing over what will happen next, so we decided to take a look back at some of our favorite moments.

Remember when every new episode was a breathtaking realization of Tatiana Maslany’s brilliance? Remember the first time one clone played another and your jaw hit the damn floor?

It’s a scenario that Orphan Black has repeated, in a number of scenes ranging from humorous to dangerously high-stakes, and watching Maslany in double action never gets old.

Alison as Sarah

Back in Season 1, Sarah was still a hot mess who wasn’t allowed to see her daughter Kira. Faced with missing a visit, she tries to send Alison in her place. The best part of this one was Felix helping her get into the character. In fact, Felix is involved in most of these transformations. Once Alison is face to face with Kira, things get a little sad though, as Kira is having none if it.

Sarah as Alison

Also in Season 1, Sarah begrudgingly has to get involved in Alison’s middle class social life, hopping in and out of the role during a disastrous party while Alison is passed out drunk and Donnie is locked in the basement. Keep in mind the two still don’t particularly like each other at this point.

It’s not the last time Sarah ends up in this position — another memorable time was at Alison’s rehab center. What is the point of a show about clones if you don’t include mistaken identity hijinks?

Get along, you two.

Sarah as Cosima

Sarah poses as Cosima in Season 2 to break into Dyad and punch Rachel in the face. She somehow manages to get through a science party without raising suspicion or revealing that she can’t see through Cosima’s glasses. Delphine notices, of course, but is chill enough not to say anything about it.

Helena’s dream

Not quite the same thing, but this delightful season opener showed us each of the characters through Helena’s subconscious. Once again Maslany nails playing her usual roles in a slightly off-kilter way, this time with a distinct Helena filter.

Cosima as Alison

Cosima tries to stay out of the identity swap game, but gets roped in by Felix to cover for Alison during a Season 3 campaign event. Clone swaps are always the most fun when they involve Alison’s uptight WASP community, and Cosima is the worst actor in the Clone Club. It’s cool, she’s got mad other skills, but sister almost blows Alison’s campaign with this slip-up.

...supporter. Saved it!

Sarah as Rachel/Alison as Sarah double-header

The first episode of Season 3 upped the ante with its tensest identity swap ever. Delphine needs Sarah to pose as Rachel for a meeting with some scary Dyad big-wig, who turns out to have be Rachel’s secret lover. Meanwhile, Sarah is supposed to be in Rachel’s custody, so a terrified Allison is roped in at the last second.

The stakes are so high in this scene because both Sarah and Allison are deeply shaken and unsure if they should be trusting or helping Delphine. Their fear and desperation is palpable, and they barely get away with it.

Maslany said of this scene that embracing her own discomfort is what lets one character shine through the cracks of the other.

Helena as Allison

Helena gets mistaken for Sarah once or twice, but merely by having the same face and not saying anything. Nothing will top Helena, feral, Ukrainian assassin, passing as Alison, type-A school board trustee, in front of homicide detectives.

Donnie doesn’t exactly help much, explaining her accent as “one of those colds, that messes with your….syntax.” Of course, it only works because the detectives have never met the real Alison before, but Helena pulls it off better than expected, proving that she’s always more observant than she seems.