In "Episode III – Revenge of the Sith", R2-D2 helps Anakin and Obi-Wan in their mission to rescue Chancellor Palpatine (Ian McDiarmid) from Count Dooku's (Christopher Lee) capital ship, the "Invisible Hand". He is attacked by battle droids, but defeats them through ingenious tactics. After Anakin falls to the dark side of the Force and becomes Darth Vader, he takes R2-D2 with him when he goes to assassinate the Separatist council, but tells him to stay with the ship. After the Galactic Empire is established at the end of the film, C-3PO's memory is erased to keep the knowledge of the locations of Vader and Padmé’s newborn children, Luke and Leia, a secret from their father. However, R2-D2's memory is not wiped; as a result, R2-D2 is the only surviving character at the end of the saga who knows the entire story of the Skywalker family. Both R2-D2 and C-3PO end up in the possession of Captain Raymus Antilles (Rohan Nichol) onboard the "Tantive IV".