Hey. Nice save, Jerk-off League— Harley Quinn
The Justice League is a group of professional "A-list" superheroes.
They appeared as a team in the present time for the first time in the episode "Devil's Snare" to stop Scarecrow's mutated tree monsters from taking over Gotham. However, they mistakingly believe Harley Quinn and her crew are behind in and banish them to the Phantom Zone. However, before getting pulled in through a portal, Poison Ivy grabs Wonder Woman's Lasso of Truth, proving they weren't behind this. They let them go and question why is behind this then but before they can get an answer, Queen of Fables shows up and traps them in her storybook as revenge for the past.
In "Dye Hard" as Doctor Psycho take control of Darkseid's parademons with the goal to take over the city, Harley realizes she needs to take responsibility and start cleaning up her messes, starting with bringing back the Justice League to take down Psycho.
Later in "A Fight Worth Fighting For" after Harley, Joker and Batman manage to get the book back, Zatanna uses the same spell she used to free Queen of Fable from her imprisonment to free them from the book. They later explain that their experience in the book was terrible.