Brian Cox has joined the cast of the animated holiday film That Christmas. Cox, who plays Logan Roy on Succession, will voice Santa Claus in the upcoming movie. Fiona Shaw, Jodie Whittaker and Billy Nighy will also have roles. The movie is based on the children's book series by Richard Curtis. That Christmas follows the "residents of a charming seaside town where things turn upside down one Christmas." The movie will premiere on Netflix later this year.