It's been a long wait for "Outlander" fans but from what we're hearing about season 4 of the hit Starz show, it will have been worth the wait. 

For one thing, there will be a dramatic reunion between Jamie (Sam Heughan) and his daughter Brianna (Sophie Skelton). 

And according to Variety magazine, filming for the major moment in season 4 has started.  Heughan revealed at an FYC panel for the show  that the scene is significant in terms of what else happens in the season, although he didn't divulge specifics.

"I'm going back tomorrow to shoot that scene. I just got the scripts two days ago, and we start shooting this week. This season, it's a huge moment and will be the catalyst to a lot of the drama that unfolds," Heughan said.

Some of the tension is around the question of time travelling and whether Brianna should leave the 20th century to join her mom Claire and live in the past with her dad. 

It's certainly a dramatic period in history and that drama is being brought to life in season 4, which will see Jamie and Claire try to make a life for themselves in tumultuous America. 

"There's slavery, there's American Indians, there's a rebellion brewing up in New England that will become the American Revolution. And they land right smack dab in the middle of all this," said showrunner Ronald D. Moore at the panel, according to Variety.

Executive producer Maril Davis shed light on some of the inner conflict that Claire might be experiencing in season 4.

"The only reason she wouldn't want Brianna to come through is because it's obviously a dangerous time, and I think you'd want your daughter probably to stay in a time where it's not quite as dangerous," she teased.

"Outlander" is based on the hit series of historical novels by Diana Gabaldon and the fourth season correlates with the fourth book in her series, "Drums of Autumn."  Season 4 is set to air on Starz in the fall, although an exact premiere date has yet to be announced.