A sudden and powerful evil force poses a fatal threat to the earth, and no superhero can resist it alone. SHIELD, which has long been committed to protecting global security, was caught off guard when its commander, Nick Fury, the One-Eyed (Samuel L. Jackson) realizes that he must create the "strongest alliance in history" and gather superheroes from all over the world to fight together to save the world from dire straits and resist the invasion of the dark forces. So six superheroes-"Iron Man"(Robert Downey Jr. ),"Thor"(Chris Hemsworth),"Captain America"(Chris Evans),"Hulk"(Mark Ruffalo),"Black Widow"(Scarlett Johansson) and "Eagle Eye"(Jeremy Renner)...