A Slarvian captain was sent to Earth to prepare the way for his species' invasion of Earth. He was to retrieve the Slarvian Queen's eggs from the spaceship which had crashed into the ocean.
When the TARDIS almost collided with the captain's ship, he rescued it and the First Doctor and Susan. Since they were not human, he treated them well.
He and his ship, as well as the Queen and Slarvian Emperor's ship, were dematerialised with the TARDIS and removed from Earth. (PROSE: Childhood Living)