The most dangerous man in Metropolis is...Jimmy Olsen?! Injected with a synthetic virus when he was an infant, Jimmy now comes under the power of evildoers who transform him into a mind-controlled assassin.
Jimmy's doctor, Dr. Golden, is murdered and Lois and Clark investigate to find out who killed him. Their investigation leads them to discover about a project that started twenty years ago when a military doctor, Dr. Wilder, injected three infants with a virus that would allow him to control their mind when they would get older, one of these kids was Jimmy. The plan was to turn these kids into assassins but when he was discovered, he was discharged.
Now, Dr. Wilder is dead but his wife, Claudette and her daughter Dr. Katherine Wilder, try to complete his project. They manage to activate the virus in all three kids and while the first one dies, Jimmy and Sarah, try to kill Lois and Clark while being under orders.
Superman stops Sarah from killing him and then stops Jimmy from killing Lois, while Claudette and Katherine get arrested by Scardino, who had come to visit Lois.
Jimmy and Sarah go to the hospital to remove the virus from their system. Meanwhile, Lois tries to talk to Clark about her feelings but every time she does, Clark runs off because someone needs Superman. Lois, who cannot understand his behaviour, is frustrated and ends up accepting Scardino's proposal to go out for a date.