Swamp Thing has a blind date with Poison Ivy, which leads to her controlling him in her plot to overrun Gotham City with plant. It is up to Batman to find an antidote to free Swamp Thing from Poison Ivy's control. Meanwhile, Poison Ivy is collaborating with Harley Quinn to help her keep Swamp Thing in check. So Superman, Firestorm, and Vixen work to fight Poison Ivy and Harley Quinn on their home turf.
The Justice League is back, 'with lightning-paced action and heroics'. This show will be including everyone: Superman. Batman, Wonder Woman, Hawkman, Green Arrow, Zatanna, Shazam, the Flash, Blue Beetle, Plastic man, Martian Manhunter, Lobo, Zatanna, the Demon, Dr. Fate and fan favorites like Harley Quinn and many more. Justice League Action, will also reunite the Batman Animated Series voice talents of Kevin Conroy as the Batman and Mark Hamill as the Joker.