Warner Bros and DC Entertainment just broke the news about the reason why the superheroes of Arrow, The Flash, Supergirl and Legends of Tomorrow will have to get together. It is an alien invasion, to be more exact the alien race The Dominators in the DC Comics.

The crossover is named after the actual comic book crossover in the 80s titled Invasion.

The four-show crossover will start with an episode of Supergirl, where the subject will be touched a little bit instead of involving the show fully in it. Then, it will progress in The Flash, Arrow, and finish with DC’s Legends of Tomorrow.

Arrow and Legends of Tomorrow executive producer Marc Guggenheim said “This year, for our mega ‘Arrowverse’ crossover, we’re taking inspiration from a DC crossover from the late 1980s known as Invasion!, which featured an alien race called the Dominators, who’d previously vexed the Legion of Superheroes. We’re using cutting edge prosthetics and computer effects to achieve a feature film-quality look which is faithful to Invasion! artist Todd McFarlane’s interpretation of the characters” about the crossover.

There are no other news about the crossover, however, here is some info for the uninformed. The Dominators are an evil alien race gathering other evil races to conquer Earth while superheroes try to save it.