Claire (played by Caitriona Balfe) returns to her own time at the end of season two of Outlander as she and Jamie (Sam Heughan) decide it is the best thing for her and their unborn baby. Claire is devastated by the separation but reluctantly agrees and returns to Frank (Tobias Menzies), who says he will raise Brianna (Sophie Skelton) as his own.
But over the course of the third season, viewers can see how much it pains both Claire and Jamie to be apart.
Claire of course was heartbroken as she believed Jamie had died at the Battle of Culloden.
Fans know Jamie did in fact survive and went on to be a prison at Ardsmuir Prison and a groom at Helwater.
Eventually he became a free man and headed to Edinburgh to open a print shop.
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But there was one key character who knew Jamie had survived and could have reunited him with Claire.
Frank was aware Jamie was alive and that Claire would return to the 18th Century to be with him.
In the Outlander novel the series is based on, Drums of Autumn, it is revealed Frank knew all along.
Roger MacKenzie (Richard Rankin) tells Jamie there was a letter from Frank to the Reverend who looked after him revealing he knew the highlander was alive.
Given that Frank was sleeping with other women while married to Claire and their relationship was pretty much over, it’s heartbreaking to learn he knew Jamie was still alive.
Explaining the difference between the show and the book, another fan replied: “The whole issue about what Frank knew, what he was hiding from Claire is a bit convoluted in the books.
“The showrunners streamlined the story somewhat, both for time, and not to confuse people who only follow the show.
“For example, instead of the fan dance in the books and among readers about whether Frank was cheating on Claire after her return, they made the choice in favour of saying he did.”