Outlander stars Caitriona Balfe and Sam Heughan on Claire's ether, the Christies, and other season 6 dangers

Jamie (Sam Heughan) and Claire (Caitriona Balfe) have weathered time travel, Culloden, kidnappings, and more to stay together on Outlander.

But they won't find any rest in season 6. In episode 1, which aired on March 6, trouble was afoot once more on Fraser's Ridge as the introduction of the brooding Christie clan brought a new, potentially malignant presence to their home. And there's secrets inside the Fraser home as well, as Claire struggles with her trauma from her kidnapping and assault, seeking relief in the ether she's been brewing to treat her patients.

Fans of the Starz series will know this just scratches the surface of what an average season has in store for the couple. We caught up with Balfe and Heughan in the midst of their season 6 press tour to get them to spill some tea (alas, not Boston Tea Party levels) about what to expect from the rest of the season.

ENTERTAINMENT WEEKLY: Caitriona, Claire is abusing her ether in order to cope with her trauma. What was your reaction when you first read that and how much worse do you think this might get for her?

CAITRIONA BALFE: When the writers first presented that, I was really interested. I was like, "Okay, this could be a really interesting way of exploring Claire's trauma in a different way." From season 1, I've been saying the same thing, Claire goes through all of these horrific events and she always just seems to pick herself up and move on. I was like, "Does nothing ever penetrate? Is she just Teflon?" It was nice to actually see the vulnerability and where she suffers and when the pain becomes too much. The only thing we were always trying to find is, "What does that look like and what is Claire's version of doing that?" People tend to use what's available to them in terms of giving themselves respite and an escape from the pain they're feeling. And how much worse does it get? She has to hit a very low point before she actually reaches out and asks for the help that she needs.

Sam, how long will it take Jamie to notice? He's generally very attuned to his wife.

SAM HEUGHAN: Caitriona worked really closely with the writers to get it right. You're talking about PTSD and what triggers that, and it was quite a lot of back and forth. It is interesting because she is very pragmatic, isn't she? And just moves on and carries on doing Claire? It's interesting to see her really struggle with that. Jamie normally would have noticed something. He's just distracted. He's got so much going on, especially with becoming an Indian agent and trying to play the different sides, but also with the Christies coming in. He can't help himself with his ego and the Christies and the two of them constantly power play. I guess he also expects Claire to come to him if she's struggling. That's normally what they do. They work through things together. So, it is a total surprise.

BALFE: Sometimes we can fall into this danger zone of like, "Oh, strong women, nothing ever gets you down." It's a real trap to equate strength with never feeling or never having to fall down. The real strength is how you pick yourself up, rather than never failing and never falling. That's important that we show all of that.

You mentioned the Indian agent job and the Christies. What would you both say is the greatest threat this season: the crown and impending revolution, the Committee of Safety, or the Christies?

HEUGHAN: The Committee of Safety and the Browns, I forgot about that! But it's more internal; it's the Christies really. Each one of them has their own storyline, but also their own way of almost decaying and attacking the Frasers stability. It's from the inside. We're used to dealing with those external forces. There's always the revolution or history or whatever it is, but this time, somehow they get under the skin of the Frasers.

BALFE: When it's so close to home, that's the thing. Jamie, he's always been such a pillar in his community and had so much respect from everybody who's around him and he's been able to inspire those closest to rally around him. To have somebody literally within our home poison that well, it's a very different place that the Frasers find themselves in.

What would you say Claire and Jamie's greatest challenge as a couple is this season?

BALFE: Claire's dealing with her own stuff, and they've always been so quick to share with each other and be there for each other. Especially when someone starts having a secret like Claire with her ether, and in the beginning, it's a secret from herself really as well. I don't think she wants to admit what she's doing. But that creates distance because you're not sharing and being open and vulnerable. That's probably the biggest challenge.

HEUGHAN: They're separated. It's not always by distances, it's by what's going on in their internal worlds. They lose sight of each other a bit. So, it's definitely their challenge because they're always stronger together.

Sam, we see Jamie make this difficult decision to become the Indian agent because he decides it's better than Brown doing the job. But how much might that put him and the whole Ridge in the crosshairs of danger?

HEUGHAN: He's given this real responsibility, and he doesn't know which side the Cherokee are going to fight on. Obviously, he has knowledge of the future that he's also on the wrong side, so he just doesn't know which side they will fall on. He knows he also has to swap sides, and pretty soon. We've been talking about this war for a while now, but it is almost here.

BALFE: War is coming!

HEUGHAN: His hand is being forced. He now has to make a decision. He has to move quite quickly.

This interview has been edited and condensed for length and clarity.

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