Rebel Planet is a science fiction adventure set in the year 2453. In this fictional representation of the future, human colonisation of the galaxy began in 2070 with the settlement of Tropos a few light-years from Earth. Earth and her colonies were conquered by an alien race known as the Arcadians in a twelve-year war around 2300. Humans have become slaves, and are kept alive only to serve their alien masters. However, a human organization known as SAROS ("Search And Research Of Space") has discovered that the Arcadians rely on a powerful super-computer to keep themselves networked together. Without this computer, they are merely zombies, incapable of acting on their own. SAROS has limited resources, but a secret plot is hatched to infiltrate Arcadion and destroy the queen computer. The reader plays the role of the last hope of humanity, an undercover agent posing as a space merchant.