Maria Doyle Kennedy has joined fellow Irish actor Caitriona Balfe for season four of the hit romantic adventure series Outlander.

US industry website Deadline.com reports that Orphan Black and Downton Abbey star Doyle Kennedy will play Jocasta, the aunt of lead male character Jamie (Sam Heughan) in season four. 

Caitriona Balfe and Sam Heughan

The fourth season, which continues the time travelling adventures of Balfe's character Claire and Heughan's Jamie, began filming in Scotland this week.

Season four is based on Drums of Autumn, author Diana Gabaldon's fourth title in her eight-book Outlander series.

Doyle Kennedy has been joined in the Outlander cast by another former Downton Abbey star, Ed Speleers.

Ed Speleers

He is set to play Irish pirate and smuggler Stephen Bonnet in the 13-episode fourth series. 

Outlander airs on Tuesdays on RTÉ One in the wee small hours.