Four more roles have been filled on Outlander: Blood of My Blood, the prequel to the Starz hit that’s based on the bestselling books of Diana Gabaldon.

Joining the cast is Brian McCardie (Time) as the leader of Clan Grant, Isaac; Jhon Lumsden (Karen Pirie) plays his son, Malcolm and a potential suitor for Ellen MacKenzie; Sara Vickers (Watchmen) has been cast in the role of Davina Porter, a housekeeper in the Lovat household and mother to Brian Fraser; and Peter Mullan (Ozark) in the role of Red Jacob MacKenzie, Laird of Clan MacKenzie and father to Ellen, Dougal, Colum, Janet and Jocasta.

Outlander: Blood of My Blood will explore the lives and relationship of Jamie’s parents, Ellen MacKenzie (Harriet Slater) and Brian Fraser (Jamie Roy) and Claire’s parents, Julia Moriston (Hermione Corfield) and Henry Beauchamp (Jeremy Irvine). The series will center on these two parallel love stories set in two different time periods, with Jamie’s parents in the early 18th century Scottish Highlands and Claire’s parents in WWI England.

Outlander, which will celebrate its 10th anniversary this summer, will be airing the back eight episodes of its seventh season this November. Production recently began on 10-episode eighth season, which will be the final lot of the series.

Matthew B Roberts will serve as showrunner and executive producer on both series. Ronald D. Moore and Maril Davis will also executive produce. Moore and Davis developed Outlander for television, under their production banner Tall Ship Productions.

Story Mining & Supply Company will also executive produce, and Gabaldon will serve as a consulting producer. Outlander: Blood of My Blood is produced by Sony Pictures Television. The series will be available across all STARZ platforms in the U.S. and Canada.