About the title
Atom visits the Hall of Justice, where he meets Batman, Superman, their pets — the German shepherd Ace and the superdog Krypto — as well as Cyborg. They are joined by Wonder Woman, Plastic Man, and Firestorm, who invite Atom to join the Justice League. Suddenly an alarm goes off, and Lois Lane reports that the Joker has attacked Metropolis. He hits the citizens with laughing gas and heads to the Daily Planet building to transform it. Batman sends an alert to Flash, and the Justice League heads to Metropolis.