Invincible Vol. 9 — Robert Kirkman

Collects INVINCIBLE #42-47!Allen the Alien returns to Earth as directed by the Coalition of Planets -- he's come to gather information from Mark about his father -- the Viltrumite Traitor. Meanwhile, the Viltrumites have come to Earth to check up on Mark's progress as the reluctant Viltrumite Agent of Earth. Also: There are fights.Series DescriptionMark Grayson is teenage superhero Invincible. He was a normal high school senior with a normal part-time job and otherwise normal life, except his father Nolan is the superhero Omni-Man, the most powerful superhero on the planet. At the age of 17, Mark begins to display superpowers, which come from his father being a member of the Viltrumite race, who, according to Nolan, pioneer the galaxy on a mission of benevolence and enlightenment. As Invincible, Mark begins working as a superhero, with his father acting as his mentor, and meeting other heroes. Then, superheroes around the world begin to die.