Original: The episode depicts a Dalek invasion of Earth led by Caan , Davros , and a red Supreme Dalek , who has kept Caan and Davros imprisoned in a section of the Dalek flagship , the Crucible , called '' The Vault '' .
Simplified: The new Dalek army was led by a Supreme Dalek , who kept Davros imprisoned in a '' Vault '' ; Davros said that he and the Supreme Dalek had reached '' an arrangement '' .