Starz's 'Outlander' Trailer Focuses on Claire's Dueling Romances (Video)

Caitriona Balfe and Sam Heughan star in the epic drama launching this summer from Ron Moore.

Starz has released a new trailer for epic drama Outlander.

Based on Diana Gabaldon's best-selling books, Outlander revolves around Jamie (Sam Heughan), who ignites a passionate affair with Claire (Caitriona Balfe), a married combat nurse from 1945 who is mysteriously swept back in time to 1743 and thrown into an unknown world where her life is threatened. Claire is pulled between two vastly different men in two irreconcilable lives.

Q&A: Ron Moore on Adapting 'Outlander,' 'Helix's' Future and Taking On James Bond

"People disappear all the time. Most are found -- eventually. Disappearances, after all, have explanations -- usually," Claire says in voiceover as we see her transported from her happy mid-20th century married life to the uncertain times of the 18th century.

It's also in the new trailer where Claire and Jamie begin to cement their relationship, with Jamie reassuring Claire: "You need not be scared, so long as I am with you." "And when I am not with you?" "Be careful."

VIDEO: Watch the First 'Outlander' Trailer

Executive producer Ron Moore told The Hollywood Reporter in February that cable was the only place for Outlander. "I don't think it could have worked in broadcast," he said. "The elements we would have had to change from the book, they would have freaked out about a lot of the sexual stuff. … We never would have been able to touch that on broadcast television. I also don't think that they would have gone for the first-person narrative. There are a lot of things you could not have done in broadcast. This had to be cable."

Watch the new trailer below.

Outlander premieres in the summer.

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