Edward Repple

Repple believed himself to be Shade Vassily, the exiled ruler of Katuria. He was in fact a Clockwork droid created as a decoy by the real Shade Vassily, who was hiding on Earth. He met the Doctor and Rose Tyler in 1924 when they were stranded in London.

Biography
Repple was created in London, in the early 20th century. He claimed to be the exiled ruler of a land called Dastaria, which did not exist. Repple believed that a man named Major Aske was his jailer, yet they became friends. Aske claimed to be a psychiatrist and said Repple suffered from delusions and was his patient.

After Aske's death, Repple admitted to the Doctor and Rose that he was not actually the Elector of Dastaria, but Shade Vassily, the cruel ruler of Katuria. However, the Doctor deduced from the constant ticking that he heard in Repple's presence that Repple was actually a Clockwork droid. Repple had been created as a decoy by Wyse, the real Shade Vassily.

With the Doctor and Rose, he stopped the real Shade Vassily from escaping Earth. During the struggle, Rose was nearly crushed between two cog wheels inside Big Ben. Repple saved her life by using his arm to jam the wheels, but lost his arm in the effort. His arm was replaced by the Doctor, who used an arm from one of Melissa Heart's Clockwork knights.

Though he was Clockwork, Repple felt human. The Doctor showed him that he didn't have to have blood to be human and encouraged him to enjoy life on Earth. Rose Tyler asked him to visit her in eighty years time. It is unknown if he did.