Robin, Aqualad, Kid Flash, and Speedy are finally ready to join the Justice League as full members. However, they soon discover that are to be treated as "junior members." An enraged Speedy leaves, while the other three strike out on their own to investigate a mysterious fire at Cadmus Laboratories. The trio soon discovers that Cadmus conceals a major conspiracy, and one of its goals is to create a clone of Superman for their own ends.

Speedy refuses to join the team, leading the members of Young Justice to wonder if their team is nothing more than a big joke to keep the young heroes "in their place". Meanwhile, Miss Martian feels that she doesn't belong on the team. The team battles a villain named Mister Twister, who they mistakenly believe is really Red Tornado testing them