Author Diana Gabaldon on the "remarkable" dedication of Outlander fans

"I don't know if that happens with other shows. Star Trek certainly, Game of Thrones to an extent. But it's the sort of shows that create a world people want to step into a live inside. That's what the fans do. They make the world themselves. It's a fascinating phenomenon."

Gabaldon is also amazed by the way her book series - and the TV show which is based on it - has bought people together.

"The odd thing about the books is the communal aspect," she says."That is that fans of Outlander want to talk to each other. They will make immediate friends standing in signing lines or meeting in bookstores. It's suddenly, 'Oh, you like Outlander? What do you think about this?' Suddenly they are best friends.

"These groups spring up which are deeply social. Outlander is what draws them together and it's a focus for their activities but it's basically drawing in like-minded people together. It's certainly nothing I ever foresaw or intended, but I'm very gratified that it works that way."

The TV show might be attracting more people to the Outlander fandom, but Gabaldon has always been aware of the story's followers.

"They've been with me for the last 25 years. There just gets to be more of them. They don't ever seem to tire of it! I just hope that the story has enough complexity and enough ambiguity to keep people constantly interested."

Outlander continues on Sundays on Amazon Prime