Outlander creator Diana Gabaldon has revealed the reason she told Sam Heughan, who plays Jamie Fraser, how the eighth and final season ends, but not his co-star Caitriona Balfe, who plays his wife Claire.

Diana has previously disclosed that she had shared the ending with the leading man, which led a fan to enquire as to why on Twitter.

"Sam knows the ending, but why didn't you tell Caitriona?" they asked.

In response the best-selling author wrote: "There was no reason to.

There was a reason Ron and Sam should have known."

Diana penned the novels upon which the drama is based, but with 10 books and only eight seasons of Outlander it would appear that the ending will be somewhat condensedThe currentseason seven has already started escalating the pace of the storytelling with the first four episodes of current series the conclusion of book six.

The sixth book A Breath of Snow and Ashes, was initially given a 12-episode order, but delays caused by COVID scaled it back to eight.

Executive producer Maril Davis has confirmed that the rest of the 16-episode season will cover books seven and eight leaving the way clear for the final season to cover the concluding books.

Caitriona told Entertainment Weekly she's grateful to have the opportunity to give the series a proper send-off with one more season.

"We didn't know there were an awful lot of conversations going on about whether there would be another one or not," she said.

"What Sam and I personally felt was that we would like to see it finished up in a proper way and not wrapped up in two episodes or something. It didn't feel like that was fitting."However, fans may have to wait quite a while for the conclusion of the epic saga as the current season has been split into two parts, with part one ending this week and part two believed to be debuting in 2024.

That would likely push season eight back to at least 2025 and shooting has yet to commence.

Caitríona gave an update during a recent interview, revealing that filming is currently on hold due to the ongoing writers' strike. 

When asked when filming was due to begin, the Irish star told RadioTimes.com: "Well, we had a date. And now with the writers' strike, who knows? So we have to just wait and see."