So Deadpool the movie comes out Friday, and you may be understandably asking yourself, who or what is Deadpool? If you watched the trailers, you know Deadpool is some kind of costumed superhero, or at least he looks like one in his red spandex bodysuit. You may be surprised to learn this slightly obscure Marvel superhero has a deep history that long predates his forthcoming blockbuster.

Wade Wilson was a mercenary — violent, loud-mouthed and not particularly heroic. In fact, he was probably the last person you’d expect or want to be a superhero. When Wilson was diagnosed with terminal cancer, he desperately sought out a cure. He found one in the Weapon X program, a shadowy project funded by the Canadian government in the hopes of creating the ultimate living weapon. Marvel fans may find the Weapon X program familiar, and that’s because it is the same project that gave Wolverine his adamantium claws.

The project’s administrators experimented on Wilson, curing his cancer and endowing him with incredible powers. Wade found he had enhanced physical strength and endurance, as well as the ability to heal from any injury. But all this came at a cost: The experiments horribly disfigured Wade’s body and took a huge toll on his mental health.

In comic books, after the hero gets their superpowers, they usually finds renewed purpose in life, shedding their selfish ways in favor of helping the common man. Well, not Wade. After receiving his new powers, Wilson rechristened himself “Deadpool” and essentially went back to what he was doing before: morally questionable mercenary work, except now he had superpowers and a less-than-stellar grasp on reality.

And that is what is so utterly unique about Deadpool: He is not really a hero. In fact, in his first comic-book appearance in 1990, Deadpool premiered as a villain, an enemy of the X-Men. Since then, Deadpool has alternated between villain, hero and insane force of nature that other comic book characters just have to navigate around.

Deadpool has been an unconventional superhero, and he is bound to make an unconventional superhero movie.