Season 3 of The Expanse comes to a close with next week’s two-hour season finale. A season finale that was almost a series finale but, thanks to the quick and hard work of cast, crew, writers, and fans, will only leave us in suspense for a few months rather than… well, the rest of our lives.

Cas Anvar, who plays the Rocinante‘s Martian pilot, Alex Kamal, was kind enough to talk to us about the show, the science, season 4, and the power of fandom.

Shiri Sondheimer: Have you read The Expanse books?

Cas Anvar: I read them as we go, one to one and a half per season. I like it to be fresh when we start filming, though I finished book four a bit ahead because of the cancelation. A lot of the information doesn’t make it into the script but it’s good to know as background.

SS: What about the rest of the cast? Are they reading along with you?

CA: Everyone has their own thing. Wes [Chatham, who plays Amos Barton] reads one a season but not too close to filming because the scrips are different than the books and there can be confusion about what the characters might know or have done in the books but not on the show. Dominique [Tipper, who plays Naomi Nagata] hasn’t read them at all; she wants to be surprised.

SS: Alex and Amos have more interaction on the show than they do in the books. What’s the crux of their dynamic?

CA: It’s lonely in space. [James] Holden [Steven Strait] and Naomi are a couple. Amos needs a moral compass, somewhere to place his trust, but he’s okay alone. Alex is private, introverted, but he’s also a normal person. He needs someone to bounce ideas off of. He’s more accessible than the rest of the characters, a married guy, having domestic problems. He was in the military. The other characters have dark backstories. Alex has an identifiable life. His only passion is ships but he needs to talk to humans. Holden is bearing the weight of the world since the Canterbury blew up; he won’t rest until he’s redeemed himself from the deaths he thinks are his fault. Naomi is introverted, focused, and because she and Holden are together, they aren’t as accessible to Alex. Amos is the most accessible, and he and Alex both like things to be chill – chill and have a drink. They’re good drinking buddies, and they get a lot done at the bar. The same “stop chasing your white whale and save the family,” mentality. That’s why people came up with AmEx.

SS: Alex is sort of the Hawkeye of the Roci‘s crew. He’s the human that holds them all together.

CA: Exactly. He’s the most accessible.

SS: What are some of your favorite Alex moments so far?

CA: The “Donkey Balls” episode. [Ed: For the record, this is 100% my favorite Alex moment.] When he sits in the Roci for the first time, the first time his purpose manifests. When he’s singing Hank Williams. When he pilots through the slingshot and he’s talking to the Roci – it’s like they’re in a relationship. I also loved the episode this season when the other Martians took over the ship and Alex was standing there, eating red kibble and schooling them a little. They’re my people, young people, hot heads and I’m trying to talk them down. I also love all the moments with Bobbie [Draper]. Frankie [Adams, who plays Draper] and I have great chemistry, and they share the Martian culture moments. I love Martian culture. And the bonding between military personnel – even though Alex is retired – is different than civilians. For Alex, finding another military person is very special.

SS: If you had to choose – as Cas not as Alex Kamal – Belter, Martian, or Earther?

CA: Belters are the most compelling. They have a lot of anger and rage, but we know a lot about them and about Earthers through Errinwright [Shawn Doyle] and Avasarala [Shohreh Aghdashloo]. I think I’d choose Martian, though. I love the Martians. They’re focused, driven, and they have a common purpose. They’re disciplined, organized, they’ve made a garden out of a rock. I admire that, the mentality, the focus on the goal and we haven’t learned a lot about them yet as a society. Alex is on the Roci and Bobbie is in the military so we haven’t really had a chance to explore the culture.

SS: I’ve seen you and Wes do some videos about the actual science in the show. What was the impetus for that?

CA: The Science of the Expanse! I love science, space, and tech.

SS: Did you know about these elements before you started working on the show?

CA: I’m a nerd; I knew some, but I had no idea what I was walking into. Our show runner, Naren Shankar, is a physicist and Ty Franck and Daniel Abraham are really knowledgeable. The science is spectacularly accurate and 98 percent vetted. The little bit that’s creative license is based on real things. The Epstein Drive doesn’t exist yet but there are theoretical models. It adds to the drama and the danger. Space is a character and it’s trying to kill everyone 24-7. It’s a compelling environment. You’d think it would be boring when you can’t communicate with your army because there’s a 20 minute delay, and by the time you hear back from them they may all have blown up but it creates tension. The way they have to administer blood thinners and sedatives during maneuvers – you could die not because you get shot but because the ship is trying to kill you. You have to get the air out of the ship so it doesn’t vent – we don’t have shields or force fields. If you get hit by too many PVCs, if you don’t vent, you suffocate or there there are too many holes and the ship cracks apart.

SS: I thought spinning up the drum of the Behemoth to establish gravity was a great way to bring everyone together at the end of this week’s episode. That the Belters could do that and save the injured.

CA: Wasn’t it? Who would think about it, that you need gravity to heal from even a minor injury.

SS: I’m a nurse, and I didn’t consider it.

CA: Why would you? But you need gravity to heal. Without it, you bleed to death. Think about it; if you run out of thrust six inches from your ship and you don’t have enough momentum, you die. You can be right there but if you can’t reach your ship, you’re dead.

SS: It’s terrifying.

CA: It is! It’s amazing.

And there you have it.

Cas is a scholar and a gentleman, and I had a lovely time talking to him. Just before we hung up, he asked me to make sure I included this:

Please let all the fans know that we have season 4 and maybe 5 and 6 because of them. From Cas and the entire team, we love you, we thank you. We have a lot more incredible stories to tell and because of you, we get to do it. Thank you.

Sounds like we may get some more info on season 4 at San Diego Comic-Con. Hold on to your vac suits, Screaming Firehawks. It’s going to me an amazing ride.