With the events of both World War Hulk and Civil War leading to curtain call for S.H.I.E.L.D. and the rise of H.A.M.M.E.R., Norman Osborn's new organisation, there isn't really anyone the government can depend on when it comes to superhuman threats. This leads to anxiety and paranoia when Everett Ross finds evidence that proves several important figures, both politicians and superheroes, have been replaced by Skrulls, in an attempt to destabilize earth and make it ready for complete invasion. With no one else to turn to, General Ross once again assembles the Thunderbolts, villains and anti-heroes who have been locked up and didn't have any chance to be replaced, to find out who isn't who they say they are and take them out.
