It began when an alien named Lord Hyronimus Grayle sent out a telepathic call to 22 men and women who grew up together in Southern Illinois. He told them that he had given them the gift of different super-powers, and they had a destiny to defend the world from an alien conquerer named Sol Terminus. Nine of them agreed to step forward to accept the responsibility of becoming heroes, and the Adventurers were born.

In truth, the Adventurers were not "given" their powers at all, but were born with them. Each team member had an alien parent---one of the several alien fugitives that had arrived on Earth twenty years earlier. Sol Terminus was a bounty hunter who had arrived to bring Grayle back home for trial. He succeeded, leaving the Adventuers without a mentor. Tragically, one of their own members was killed in the confrontation as well.

Since then, the heroes have registered as licensed super heroes as part of the Superhuman Samaritan Act, and they've moved into a government funded headquarters in Chicago. Since their initial battle with Sol Terminus, they've helped to dismantle the criminal empire of Ceaser Lithgow, the so-called "Crime Czar." They've also prevented the demon known as T'Shier-Iyla from jump-starting the apocalypse by foiling the plans of her cult, The Dark Jubilee.

While the majority of the world remain unaware of the alien heritage of the heroes, the Adventurers are called on to respond to emergencies around the world. Under the capable leadership of the Sorceress, the group continues to rise in popularity, making the world a safer place to live.