Daily Planet reporters Clark Kent and Lois Lane are covering the opening of the new Metropolis Museum when, suddenly, a gigantic skeleton of a blue whale comes to life. With lightning-speed, Superman catches the colossal creature, but the magical mischief is far from over. The impish Mr Mxyzptlk has returned from the Fifth Dimension with dozens of troublesome tricks. Even the Man of Steel is helpless against his magic powers!