Apprentice: Part 2 (S01E13)

With no signs of Robin since Slade's Chronoton Detonator turned out to be a fake, the four remaining Teen Titans search the city for their missing leader. But their quest soon ends when the Titan signal alerts them to a new villain in town. When they arrive on the scene at a high-tech defense lab, they are shocked to discover that this new villain is none other than Robin himself (wearing a sinister new Slade insignia costume). Unaware that Robin is only serving Slade to save his friends from the nanoscopic probes inside them, the bewildered Titans think Robin has betrayed them. Can Robin fight his friends without hurting them? Will he find a way to stop Slade without triggering the probes? (iTunes)