When Clark (Tom Welling) rescues his classmate Eric (guest star Shawn Ashmore) from harm during an electrical storm, they are both struck by lightening, resulting in all of Clark's superpowers transferring to Eric. While Eric relishes his new life as "Superboy," Clark is torn between his happiness at finally being normal and his growing concern for the town's safety as Eric starts to abuse his powers. Meanwhile, Lex (Michael Rosenbaum) believes he finally has undeniable proof of Clark's superpowers and confronts him.