The Ood debut in the Series 2 episode "The Impossible Planet". They are used by humans as a slave race, performing all manner of menial tasks for the humans in the episode. They are described as offering themselves for servitude willingly, having no goals of their own except to be given orders and to serve. It is also claimed that they cannot look after themselves and that, if they do not receive orders, they pine away and die. The episode also alludes to a group called "Friends of the Ood" who oppose Ood slavery and seek to have them freed.