In July 2015, it was announced that Otto had departed the show due to her commitments to the fifth season of Homeland and she was replaced by Sidse Babett Knudsen.
After the last episode of the first season was broadcast, Nolan and Joy revealed that they had operated on a strict need-to-know basis with most of the actors, in order to "keep the story as fresh and present for them as possible."[REF]