The upcoming HBO Max prequel of the 2021 movie titled 'Dune: The Sisterhood' has cast Emily Watson and Shirley Henderson.

The show, set 10,000 years before 'Dune', is based on the novel 'Sisterhood of Dune' by Brian Herbert and Kevin J. Anderson.

The series “follows the Harkonnen Sisters as they combat forces that threaten the future of humankind, and establish the fabled sect known as the Bene Gesserit.”

Watson will play Valya Harkonnen and Henderson will play her sister Tula Harkonnen. The character descriptions say the two sisters “have risen to power in the Sisterhood, a secret organization of women who will go on to become the Bene Gesserit.”

Watson was nominated for the Academy Award for Best Actress for her debut film role in Lars von Trier's Breaking the Waves and for 'Hilary and Jackie'. She also appeared in 'Angela's Ashes' and 'Chernobyl'.

Henderson is probably best known for her role as Moaning Myrtle in the 'Harry Potter' movies and Sally in 'Intermission'. She also recently played Agatha Christie in 'See How They Run'.

'Dune' director Denis Villeneuve will act as executive producer alongside Jon Spaihts, Scott Z. Burns, Matthew King, John Cameron and Cait Collins with Brian Herbert, Byron Merritt and Kim Herbert for the Frank Herbert estate. Anderson serves as co-producer.

'Dune: Part Two' is currently in the works. Christopher Walken will play Emperor Shaddam IV in the sequel. Florence Pugh and Austin Butler are also joining the main cast.