Picking up where season three of the TV series left off, Mainframe's heroes are rested and ready to face the net's most dangerous supervirus - Daemon. She has infected the Guardians, using them to spread her word across the net. Now, she wants Bob, the only Guardian to merge with his keytool making him the perfect messenger. Meanwhile, Ray Tracer has been captured, Mouse is in a rush to save him, Matrix is annoyed by his copy (Little Enzo), AndrAia is teaching both Enzos patience, Little Enzo is repeating the mistakes of his grown counter part, and Dot is burdened under each the problem with no way to solve any of them. Every citizen of Mainframe must play a part and risk sacrificing something to stop Daemon.
—Max Vaughn