Tonight’s Star Trek: Discovery was another crazy episode with lots of drama and action in the Mirror Universe, and the producers of the series, along with actor Jason Isaacs (Lorca), hit the interview circuit to add some insight into the events of “What’s Past is Prologue.”

MAJOR SPOILERS FOR THE EPISODE BELOW!

So after eleven episodes, Jason Isaac’s run on the show ends with a sword through the chest and a mycelial ball of energy to the face: but it wasn’t a surprise to the actor, as the plan for Lorca was always intended to conclude this year.

Speaking with Entertainment Weekly, Isaacs said he was aware of the former Discovery captain’s origins when he was hired, and detailed what happened when he arrived on the Federation’s USS Buran:

“I knew [about Lorca’s story] before I took the job. It was pitched to me that he was from the Mirror world. I said, “What’s he doing here? How did he get here? What does he want? And how’s he going to go about achieving those things?” And at first they went, “We’re not really sure, it could be one of 20 different things.” And I blinked slightly and I said, “I’m not sure I want to do the job if I don’t know exactly what he’s after, because then I won’t be able to act!” Then we had a bunch of discussions and came up with a plan which we pretty much stuck to all the way through.”

He expanded upon that sentiment with IGN:

“I was very keen when I took the job on that we work out exactly what his plan was, how he was gonna get home, and what he wanted to do when he got there. And that wasn’t really clear when I first started talking to them. And I explained that I just couldn’t — I couldn’t do my job very well and I didn’t wanna play the part unless we would all figure those things out. And they said absolutely, we agree to be a part of the discussion. So there were a number of times before we started shooting that we sat and said, well, it could be this, it could be that, it could be the other. But once we settled on what he was after, at least, that stayed the same. And they changed… you know, stories were being written all the time, pages were being delivered on the day. But, no, it was always gonna end up with me, Michelle [Yeoh] and Sonequa [Martin-Green] in a room, knocking seven shades of s#!t out of each other.”

He also told EW about filming that epic fight scene from the last moments aboard the Charon:

“The fight was epic and shot in a day. It should have been a month, but it’s TV, so what are you going to do? Michelle is a brilliant fighter and can fight at six times the speed that my eyelids work at, so it was tough to keep up with her and look like I was fighting her and not just being beaten up by her. Plus she’s also very delicate, so when I hamfistedly swing my big legs and arms around, I was being careful not to break this exquisite creature. She ended up very bruised. The one that was a surprise was Sonequa because I hadn’t seen her fight; obviously, we’ve all seen Michelle fight. I mistook Sonequa a couple times for her stunt double across the room because she moves with such clean lines and dynamic energy. She looks like a Nintendo version of herself.”

Over at Buzzfeed, the actor spoke on the restrictions in speaking with the public — and fans — about Lorca, and that he had difficulty “lying” to keep the secret.

“It’s been embarrassing/awkward/torturous lying to so many people, including close friends and family members, but particularly to the press, and indirectly to the public. But Star Trek fans particularly are incredibly smart and highly attuned to every nuance in the story. So you just couldn’t give them a clue.”

And with IGN:

“People… are always asking, how do you feel signing up for seven years for something, and what it’s gonna be like being on the ship forever? And you’ll be known as this for a long time, and I’m thinking, I’m dead in three weeks! So that’s been an odd feeling. Even people in Toronto [where the show shoots] around me who I’ve become friendly with… who assume I’m gonna be visiting, coming back for six months every year, and I couldn’t tell anybody. I felt slightly ashamed.”

Series executive producer Aaron Harberts also shared the tidbit that while the inclusion of the Mirror Universe as part of Discovery‘s first season came from former showrunner Bryan Fuller, Lorca didn’t start out as being from the Terran Empire until Harberts and co-showrunner Gretchen Berg took command.

Harberts explained that the writers knew from the start, when creator Bryan Fuller was first planning out the show’s serialized storyline, that the inaugural season of Discovery would end up in the Mirror Universe. (Fuller eventually left the show due to creative differences with CBS, elevating Harberts and Gretchen J. Berg to showrunner status.) But at first, the writers planned for Lorca to be a hawkish captain given a chance to shine thanks to the Federation’s war with the Klingon Empire. It was only after the writers began discussing why Lorca would be so skilled with warfare that they hit upon the idea that he’d secretly be from the militaristic world of the Mirror Universe. Typically, showrunners keep their actors in the dark about any major twists in store for their characters — it helps contain the surprise, and saves the actors from having to actively lie about the role. But given that Lorca would have his own secret agenda throughout the season, Harberts and Berg realized they had to tell Isaacs about their plan for the character from the start.

Finally, speaking to IGN, the actor detailed how the seeds of Lorca’s deception were planted throughout the season to date.

“I had to know the whole thing, because I had to plant little seeds and secrets. I had to be able to give clues here and there, and more importantly, I had to play him honestly like a guy from the Mirror Universe who was lying and hiding. So if I hadn’t known, I wouldn’t have been able to play it. And even when I’m doing things that seem noble or heroic, they’re always only to engender more loyalty in Michael Burnham, or to make sure that I keep the ship so that I can work on the spore drive and get home again.”

But what about the “good” Gabriel Lorca, who shared so much history with Admiral Cornwell and got universe-swapped with Mirror Lorca and the Buran? Isaacs shared a bit of backstory with EW.

“There was a Prime Lorca, he was captain of the Buran in the Prime world. He swapped with him and found himself captain of the Buran. This never came out, this backstory detail we never put in the dialogue: Although Lorca spins this story having had to sacrifice the men on Buran and had to blow them up to save them from Klingon torture. Actually, if I remember correctly, there was some kind of DNA identification that would have exposed Lorca as not being Prime Lorca, and so he blew up the ship and killed everyone on it.”

But where is “Prime Lorca” now? The actor can only speculate to IGN:

“We don’t know anything about the fate of Prime Lorca. Is he as interesting as Mirror Lorca? What is his taste in fashion? Does he wear leather coats, does he wear puffy-sleeve shirts, does he have a goatee, does he blow-dry his hair? Who knows? We know nothing. Or is he that different? Frankly, I mean, how different are any of us from the Mirror version of ourselves? They say we’re all five meals away from being savages. This particular administration in America has brought some of the ugliest parts of human nature out from in the shadows. And who knows what other exposures the Mirror world might have done. Who knows where he is.”

The Gabriel Lorca we’ve been watching on Star Trek: Discovery is dead and burned, and Jason Isaacs bid his farewell to the Trek family tonight — and on After Trek, series star Sonequa Martin-Green also Skyped into the program to say goodbye to the departing actor.

That’s not the end for Jason Isaac’s time in the Star Trek world, however, as he’s already signed up to attend April’s Destination Star Trek – Germany convention, August’s annual Star Trek Las Vegas convention and the Destination Star Trek – Birmingham convention this October in the UK.