There's a team of DC superheroes in writer/director James Gunn's Superman movie - but they're not the Justice League. Instead, they're the Justice Gang, a group of heroes for hire organized and bankrolled by Sean Gunn's Maxwell Lord.
Consisting of Green Lantern Guy Gardner (Nathan Fillion), Hawkgirl (Isabela Merced), and Mister Terrific (Edi Gathegi), the Justice Gang does bear a strong resemblance to certain eras of the Justice League in comics. But there's no comic book team called the Justice Gang. Instead, the team in the film seems to take its inspiration from two different comic book sources - and one of them is actually a team of villains.
