Fan-favorite creators Kurt Busiek and George Pérez craft a new era for Earth's Mightiest Heroes! The Avengers forge an uneasy alliance with the Thunderbolts to face Count Nefaria - but the true threat comes from the stars, as Earth is declared a cosmic maximum security prison for alien criminals! COLLECTING: AVENGERS 24-56, 1 1/2, ANNUAL 2000-2001; THUNDERBOLTS 42-44; MAXIMUM SECURITY: DANGEROUS PLANET; MAXIMUM SECURITY 1-3; AVENGERS: THE ULTRON IMPERATIVE