For the role of River Song, they wanted to cast Kate Winslet. One of Winslet's first acting jobs was in the BBC1 teen drama "Dark Season", written by Davies. The role of River Song went to Alex Kingston instead. She is known for starring in the popular US drama "ER". On Kingston's casting, Davies said "I bloody love her!" Kingston had liked "Doctor Who" as a child. Kingston, when first cast, did not expect her role to be more than just the two episodes. She later learned that Moffat had always wanted for Song to come back for more episodes. Kingston likes getting to play an unusual action hero female role.