Orphan Black returns Thursday, and many of you might find yourself forgetting what happened last season. Check out this crash course to remember all the important details you need for the premiere.

Every time a show ends a season there’s going to be an insanely large gap between the season finale and the next season’s premiere, and in that gap we often find ourselves forgetting what happened — Orphan Black is no exception.

Unless you’re part of the fandom that is constantly analyzing episodes and/or writing fics and drawing, and re-watching episodes constantly you’ve likely forgotten some key elements of the story that you’ll need to remember when the show returns this week.

But fear not, Clone Club! We’ve got the crash course on Orphan Black season 3 so that you can go into season 4 knowing every important thing that happened.

Delphine got shot

There’s a very good reason why we don’t say Delphine is dead in this headline. At the end of season 3 Delphine got into a fight with Dr. Nealon, in which he tried to spit some sort of worm from his mouth and into hers. She managed to get away and shoot and kill Nealon and destroy the worm, but not before Nealon had told her that she would be dead by morning.

She got to the parking lot and was indeed shot before the sun came up, but that’s the last we saw of her. We still don’t know if she’s dead or if she somehow survived the shot, but it’s very plausible because she got shot in the abdomen, not the head or heart — and as we all know, you’re not dead on TV unless it’s actually confirmed.

The “original” has been found

Ever since the series began people were wondering who the “original” clone was. Was it Sarah because she had a baby? Was it Sarah & Helena since they were twins? Who was it?! It was a mystery that we thought was going to be slated as the series mystery, not to be revealed until the very end – but then it was revealed in season 3.

It turns out the original source for not only the female Leda clones, but also the male Castor clones, is none other than Mrs. S’ mother, Kendall Malone. She was approached by Mr. & Mrs. Duncan because she matched their needs for an organ donation — and the reason she was able to produce both male and female clones was because she absorbed a male twin in the womb.

Therefore, all the Leda clones and all the Castor clones are blood related and are legitimately brothers and sisters. They’re all one big, complicated family.

After realizing this, though, Sarah had realized they need to go on the run because people were going to be looking for Kendall and Kira since they’re both huge deals in the science world. So they ran off to some cabin in the middle of a winter wonderland, and that’s where you can expect them to be when season 4 starts.

Rachel has been kidnapped by her mother

After being shot in the eye with a pencil, Rachel spent most of season 3 recuperating and healing from that horrific accident. She had suffered some pretty severe mental damage that prevented her from speaking full sentences and affected her motor skills.

She was due for surgery to help fix her eye and other damages caused by the accident, but when she woke up she was in a fancy room which she was clearly locked in and when she looked into the mirror she found that she had a brand new bionic eye from which she could see again.

But the eye wasn’t the biggest surprise! When someone walked into her room to talk to her about all the changes she’s had, Rachel turned to see Susan Duncan — her mother. Thought to be dead for years, this is definitely the biggest shock of last year’s finale.

Neolution is back

With the return of Susan Duncan so comes the return of Neolution, the extremist scientific movement that hopes to further and quicken human evolution with the use of technology. Bionic eyes, like the one Rachel received, was just one example that we were shown way back when in season 1.

We thought the concept of neolution was done for since we hadn’t really heard of it since season 1 and barely in season 2, but it’s back and bigger than ever and we imagine that Orphan Black season 4 is going to be all about it.

There are other clones out there, people

With all of the focus being kept on Sarah, Cosima, Alison, and Helena we need to remember that there are still other Project Leda clones out there. Granted, we’ve met several clones that are now dead like Katja, Beth and Jennifer and that makes it hard to keep count of which clones are still alive.

The ones we’ve met so far that are still alive and (all things considered) well are: Tony, the transgendered clone we met in season 2 that has yet to re-appear; Krystal, who Nealon had switched out for Rachel so that Rachel could be kidnapped and is now self-aware that she is a clone; and most importantly Charlotte, the 8 year old clone that is the only one who survived the last batch of cloning attempts but suffers from a physical disability.

In addition to those clones we’re going to meet at least one new clone this season, so if you think you’re having a hard time keeping track of all the Tatiana Maslany-s you’re seeing, we don’t blame you.

Project Castor: Everyone is dead but Mark

Season 3 of Orphan Black was huge because it introduced the concept of male clones. Dubbed Project Castor, these clones are the actual brothers of the Project Leda clones because they came from the same genetic makeup.

However, the male clones have a major defect. While female clones were specifically intended to be infertile, the male clones have a mental degeneration disease that ends up killing them within a few weeks/months of the first symptom showing. This disease is also sexually transmitted, and the result in females is that it makes them infertile just like the Project Leda clones.

The end result is that all of the male clones we’ve met have either died from this degeneration disease or from being killed by Helena and Sarah and the bomb that they set off at Castor camp — which unfortunately also killed Paul in the process.

We’ll likely end up meeting other Castor clones on season 4, but for now Mark is the only Castor clone left and he’s currently on the run with his girlfriend Gracie, the ex-prolethean.

Proletheans are no more

Speaking of Proletheans, they were responsible for kidnapping Helena in season 3. We found out that the Proletheans were the ones who brainwashed Helena into trying to kill the clones for them because they believe all clones are an abomination — though some of them think the clones can be used to their benefit, like the leader that tried to impregnate Helena.

But we know Helena, and she isn’t one to take things lying down. She did end up burning down the farm that held most of the Proletheans we know about — but we’re still unsure if there’s a different sect somewhere out where or if they’re the last ones ever.

Oh, and because of the Proletheans Helena is definitely still pregnant.

Don’t forget Kira

And after all of this drama, there’s just one thing that you really should remember: Kira is the only legitimate child from a clone. Sarah is the only Leda clone that isn’t infertile and gave birth, so Kira is definitely an anomaly.

Not only that, but Kira shares the same genetics as Sarah and Helena when it comes to regeneration and healing. That’s how she survived a fatal car crash. DNA from her tooth was able to help vastly improve Cosima’s health (remember, Cosima suffered from a terrible respiratory disease that has been known to kill Leda clones in the past) and hopes that her bone marrow would heal Cosima were squashed when Rachel destroyed all of it.

Kira has also been the only person in the entire series to know when a clone was impersonating another clone. We don’t think this intuition is just happenstance or coincidence, so it’ll be interesting to see if her role changes this season and she gets even more intuitive.

At this point Kira’s existence is one of the biggest mysteries of the season, and you would be doing yourself a disservice if you totally disregarded her.

‘Orphan Black’ returns April 14, at 10:00 pm Eastern