|Main aliases:||The Doctor|
|Affiliated with:||Rulers of the Universe|
|First seen in:||I Went to a Marvellous Party|
|Main actor:||Samuel West|
"Mr Song", also known as "the Doctor", was a renegade member of the ancient Kamishi species, also known as the First Race.
River Song first met him after she investigated the murder of Jenkins. (AUDIO: I Went to A Marvellous Party) He tried to stop his race's spore ships and allied himself with the group calling themselves the "Rulers of the Universe". With their help, he abducted River Song and tried to convince her that he was in fact an incarnation of the Doctor. He encouraged her to investigate the spore ships. (AUDIO: Signs)