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.moreless
The lack of relationship and interaction with Superman angers Superboy, leading him to lose control of his anger and decline training with Black Canary. When Young Justice encounters an opponent that even their Justice League superiors have experienced difficulty in defeating, will Superboy decide to help the team?
Red Arrow rejects Young Justice's help and attempts to prevent the League of Shadows from starting a war. Ultimately he finds himself working with an even deadlier ally to fight the League's assassins.
Miss Martian and Superboy go undercover at a Federal penitentiary where the world's most dangerous super-villains are kept under lock and key.
The non-powered Robin and Artemis are the only members of Young Justice who can stand against mysterious invaders who come after the team in their home base.
Aqualad's teammates discover that he held vital information from them concerning the presence of a mole, sowing the seeds of mistrust. While attempting to deal with their internal issues, the team is sent to India to investigate reports of armed animals attacking human beings... and Batman puts Captain Marvel in charge of the group.moreless
While the Justice League combats a worldwide outbreak of plant creatures, Batman sends Young Justice to deal with the villains responsible: the Injustice League.
Young Justice takes along their new friend Zatanna on their quest to find Red Tornado and learn if he's the mole.
When the Justice League is defeated by alien invaders, Young Justice must step up to fight in their stead.
The Forever People come seeking a missing possession: Sphere, which has undergone a bizarre transformation.
Artemis and Zatanna decide to go partying on Halloween night, only to discover that a youthful assassin, Harm, has set his sights on them. Meanwhile, Miss Martian and Superboy take Kid Flash to their high school Halloween dance.
Young Justice, Zatanna, and Captain Marvel's alter-ego Billy Batson are the only ones on Earth who can save the day when five villainous sorcerers make every adult on the planet disappear.
On his birthday, Kid Flash is forced to go on what is supposed to be a simple delivery mission, rather than battle with the Justice League. However, he soon discovers the mission is anything but simple.
When the team returns to the Middle East on a mission to Qurac, Miss Martian must face her secrets... but will doing so save the team or destroy them?
Superboy discovers that he may not be alone when he learns that Cadmus created another clone of Superman. Meanwhile, the League votes on new members.
Artemis discovers that she's out in the cold when Red Arrow returns to Young Justice to help them track down Sportsmaster... who is tied to her mysterious past.
Young Justice tries to find a thief using the Haly International Traveling Circus as cover for his activities, but find much more.
A new member joins Young Justice just as they must face internal struggles as the moles make their identities clear.
Young Justice takes on its most dangerous enemy after they discover who within the team is the traitor.