Superman; Superboy (flashback); Lana Lang (flashback)
Superboy finds out that something he did on his last day in Smallville as Superboy is going to allow a criminal to make $1,000,000. Superman must think back to that day and discover what it was that he did. Flashbacks of Superboy's graduation and the cake that was presented him by the town.
Legion of Super-Heroes [Bouncing Boy; Saturn Girl; Sun Boy; Cosmic Boy] (cameo); Superman [as Superman-Red; as Superman-Blue]; Lois Lane; Lana Lang; Supergirl; Lex Luthor; Mr. Mxyzptlk; Krypto; Comet the Super-Horse; Jimmy Olsen; Perry White; Lucy Lane; Phantom Zone inhabitants [Jax-Ur; General Zod; Dr. Xadu; Professor Vakox; two unnamed prisoners]
The Supermen marry Lois Lane and Lana Lang. Jimmy Olsen marries Lucy Lane. Mr. Mxyzptlk reforms.