Synopsis:
Superman regards his Fortress of Solitude in the unexplored Arctic as a secret place where he can relax and take pride in his collection of trophies, his interplanetary zoo, and his advanced laboratory. But an intruder has broken in and left messages for Superman to find, challenging him to discover his identity. Before long, Superman learns that the intruder is Batman, who has been playing a practical joke on him in celebration of the anniversary of Superman’s coming to Earth.
