"Attack of the Micro-Murder"
When a dying criminal curses Superman, it intrigues him enough to investigate & what he finds shocks him, as he finds that the individual who made the threat was not a man, but a millennium old celestial entity bent on evil named Zohtt.
Note: Supergirl does not appear in this story.
"The Man With The X-Ray Mind"
When Clark returns to his old college campus he runs across the Janitor, Mister Lundgren. Through a series of events, he learns that Lundgren can divine future events thru liquids.
"The Impossible Legend" A Vigilante story reprinted from Action Comics #176.
"When Krypto Was Superboy's Master" reprinted from Adventure Comics #310.