Original Airdate: January 13, 1990
While Professor Peter son is out of the country, the Army experiments with deactivating a sample of deadly green Kryptonite, doing away with the rays that hurt Superboy, but retaining the energy it produces. Instead, they inadvertently convert it into mysterious Red Kryptonite. Superboy is invited to look over the new form of Kryptonite,since the rock – now turned red -should be harmless. Instead, the new Kryptonite proves to be equally deadly to Superboy by making the Boy of Steel purely evil. Metallo is enlisted to combat the super-hero – now a super menace – but instead he tries to team up with Superboy and take over the world.
Guest cast: Michael Callan as Metallo, Jim McDonald as General Swan, Richard Vaigts as Warden Ordway, Barry W. Mizerski as the first scientist, Henry J. as the second scientist.