The Return is the name for the cause of the Altarin'Dakor, the prophesied return of the AD to the galaxy to assume control of it as its rightful owners. The Altarin'Dakor citizens are taught about the Return from birth and this is the ultimate goal of their lives. They will do anything to achieve this.
"The Return", the Story
The Return is also the name for Chapter Four of the New Imperium Plotline.