Outlander: All the season 4 photos so far

"We did a lot of the boat stuff," explains Caitriona Balfe (Claire). "Obviously we aren't shooting in America. For all the water that we have in Scotland, there's actually not that many large rivers like you would have in America. Anything that had to do with the journeys to River Run or places like that, a lot of that was CGI."

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"From where we left off in season 3, Ian's been through quite a bit of trauma," says John Bell. "However, coming to America, he's completely enthralled by the whole new world that he's living in."

"Once they meet her neighbors, Claire and Jamie get along very well with them," Balfe says.

"We have those moments together and he would like chill out with me on set, just come and lay back beside me," remembers Bell. "He's like a bit like a therapy animal, you know? It was nice to have him around on stressful days."

"She's looking at it!" explains Richard Rankin (Roger). "She might just be hanging out. I never really asked her what she was doing up there, but she might just be hanging out."

"There's obviously a lot going on for Brianna," admits Rankin. "She's a modern-thinking woman, so there's a difference in ideas between the two of them. They obviously love each other very much, and I think deep down they know they want to be with each other. But they just have different ideas."

Tantoo Cardinal (Dances with Wolves) plays Adawehi, a Native American woman who Claire meets near Fraser's Ridge. "They end up having this really special bond, which is quite beautiful," Balfe says.

"I think that there's a stability and a sense of calm between Jamie and Claire that we probably have not seen before, but obviously the price that she's had to pay for that is not seeing her daughter," admits Balfe.

"It was very, very cold this winter," Balfe says. "The costumes were different. Obviously when we were in Scotland we were using those very heavy wools. The costumes were much more forgiving for the weather. This season there were a lot more linens and lighter fabrics that would've been much more available in America. But we had to layer up an awful lot more than we had before."

"Jamie falls in love with America," says Heughan. "He recognizes that it's a new world and not without its dangers, but he realizes it may be sweeter than Scotland."

"Her studies [in Boston] are a great distraction," says Sophie Skelton. "She can throw herself into her work and not think about Claire or Roger or Jamie or Frank. She's obviously very intelligent so that's a way to build her life."

Aunt Jocasta (Maria Doyle Kennedy) with Jamie (Heughan) and Claire (Balfew) at River Run. "I think she's wary of Jocasta," Balfe says of Jamie's aunt. "They never really get to get past that rift that is there because of the plantation and the slaves."

"Brianna's is in Boston and Roger's life is in Oxford, so when you find them, they're in the midst of a long distance relationship, which is quite testing of them," explains Rankin. "The world was a much larger place in the '60s, so communication was quite difficult. They really couldn't see a lot of each other, and maybe only spoke to each other once a week."