Aquarius postmortem: Showrunner John McNamara breaks down the finale's biggest twists

Warning: This story contains spoilers from the Aquarius season finale.

Sam Hodiak (David Duchovny) shouldn’t frame his medal of valor just yet.

Aquarius’ first season finale left just about everyone’s future up in the air: Charmain (Claire Holt) has disappeared after getting too close to the truth. Ken (Brían F. O’Byrne) may have committed another murder. Charlie (Gethin Anthony) let Sadie steal a baby to replace his stillborn child. And Sam was rewarded for using unnecessary force on Raymond Novo’s killers — only to be reported by an unseen witness. EW talked to showrunner John McNamara about the last-minute twist, what to expect in season 2, and how to take liberties with Charles Manson.

ENTERTAINMENT WEEKLY: A lot was left open ended in this finale. What was the thought process there? Did you feel like you were taking a leap?

JOHN McNAMARA: I wanted to do everything I could to encourage NBC to pick us up for a second season. I tried to make it so they’d want to find out what happened. I think it worked! … I personally love cliffhangers. They’re frustrating as a viewer, but I also love them. And we have an idea of where we’re going to go. The writers’ room for season 2 starts next Tuesday.

Is there anything you can tease for us about next season?

I think we have a way for Sam Hodiak and Charles Manson to spend some quality time together.

Now how about this witness to what went down at Richard Theriot’s house?

One of the things with Aquarius that you always try to maintain is a sense that the world is a really unpredictable place, and you never know moment to moment what’s going to happen next. I’ve got to be honest: That was a last-minute thought. I only had it as I was writing that scene. I just thought, “You know, Sam is too happy. This can’t last!” And the guy who plays the IA investigator, Tim Griffin, is a really good friend of mine. He and I did Prime Suspect together with the creator Alex Cunningham, who’s also on Aquarius with me. And I just thought, “I never got to work with Tim this year. I kept meaning to write him a character. I’ll jam him into the end of season 1 and have a nice arc in season 2.” So he’s the Internal Affairs guy. Honestly, that’s as much thought as I put into it: Make Sam Hodiak unhappy and work with Tim Griffin.

Sam’s decision to take responsibility for what happened in that house might be the scene that stood out to me the most in the finale. Take me through that. Did he know that the commissioner would approve, or was he expecting consequences?

[David Duchovny and I] had a lot of discussions early on about the fact that [Sam] is a very violent guy … David Duchovny is the most gentle, sweet guy in the world, but I think he likes playing this character, and one of the things he likes about playing this character is that this is a man who, from the time he was a 19-year-old Marine in the Pacific in World War II, has always bent the world to his will through violence. In the last couple years for this character, the ’60s have begun to unfold, and suddenly you have the Miranda warnings and victims’ rights and the rights of the accused, and his whole methodology is not working … So David and I both thought we wanted to do a season-long boil, a guy just boiling inside. Given certain circumstances and certain opportunities and certain feelings of righteous indignation specific to that case—and specific to how he feels as a 45-year-old man in 1967, which is more and more obsolete and kind of impotent in a way—when you put all of those pieces together and put him on a certain track, and then somebody stabs him when he’s just trying to arrest the guy, he’s going to kind of lose his s—.

And the thing that I like about Sam is that he pretty much doesn’t lie — he’ll lie to get a suspect to confess or to get in the door to solve a case, but he’s a guy who’s not going to lie to himself. And I think what he was certain of, too, was that he was still safe within the power structure of the almost all-white, almost all-male LAPD of 1968. I think he knew who the commissioner was. I think he knew that he would approve … And certainly we weren’t thinking of all of the cop stuff that’s happening in the news today — that wasn’t conscious, but I must have pulled it in somehow … Early on, I said to David, “Wouldn’t it be cool if by the end of season 1, you kill at least one person, Ken Karn kills at least one person, maybe two, and Manson doesn’t kill anybody?” And David goes, “If we can pull that off, that would be very interesting.”

Ken also told Sam that they’re “the same.” Can you talk about the parallels between the two of them?

They both love the same woman [Grace Karn, played by Michaela McManus]. They’re both men of World War II. They’re both men who are very much feeling completely out of it in the ’60s — they’re both establishment guys with short hair and a lot of secrets, and I think they’re both men who, to go back to a phrase I used earlier, expect the world to bend to their will. And they both are capable of doing terrible things when the world does not bend to their will, as we see. So that duality was always there, and it was very important to me to juxtapose at the end, that each of these men who present a different aspect of male white reaction in the 1960s — both of them are killers. And that’s very intentional.

And I like that we had the female reaction in Charmain.

Charmain was a very last-minute addition to the pilot script — she was not in the first draft. So I think she was in a way kind of the least developed when we started shooting. And yet we’d cast this wonderful actress [Claire Holt], who I just really liked, and the more I would throw her challenging stuff, she would just hit it back with so much confidence. And that’s what happens on a TV show — you can tell who the writers really like, and we love Claire. And something that helped was that I wrote the pilot alone, but that’s the last time I ever acted solo on the show, and we have two really strong female writers: Sera Gamble and Alexandra Cunningham, who are both showrunners in their own right. That was a great set of voices to add to constantly champion for Charmain and for her journey. I have huge plans for her. Now, I know exactly where she’s going for the entire series. And it’s a really big journey.

Anything you can say about it?

She has not seen the last of undercover work in the Manson family. And she has not nearly risen to the heights she will rise in the LAPD.

You did something that I did not think was possible — you took the Charles Manson story and made it darker. They stole a baby! Why go that route?

One of the things in our entertainment industrial complex that I think I’m most underwhelmed by is the idea that in a lot of fiction, the answer to the question is, “Oh, he’s a bad guy. He’s a monster.” And there’s no further psychological examination. It takes evil and puts it in a very safe place that’s not us — nothing like us … And to me, the whole key was that Manson has this incredibly human frailty. Unfortunately, he turns his frailty into anger and then that anger turns into violence. So the writers and I thought, “What can we do at the end of the season that is absolutely heinous yet in his mind is motivated by love?”

That birth was just absolutely terrifying to read. I did not change one word of what David [Reed] wrote … It almost made you feel sorry for Charles Manson. Certainly you felt sorry for Mary. It’s also indicative of his character, that his own arrogance led to the death of his child. He would not go to the hospital. He did not believe it was necessary … So you know, you’re in the writers’ room and you’re talking about ideas, and someone’s having sushi and says, “What if Manson stole a baby?” And no one said, “Oh, he would never do that.”

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