As the world sinks into a deep crisis and the threat of ultimate destruction looms just over the horizon, the only hope for mankind lies in six superheroes in this animated Marvel feature. The world's most powerful superheroes have all been brought together in hopes of averting disaster, but with Captain America locked frozen in a solid block of ice for over 60 years, the powerful team must struggle to find a leader. As the reluctant superheroes combine their forces to fight for the good of mankind, the sudden emergence of an unexpected opponent from within their own ranks throws the entire mission -- and the fate of mankind -- into chaos.