Watch Iron Man: Extremis full episodes online free watchcartoononline.
Synopsis: When a mysterious, experimental serum called Extremis gets stolen, and the lead researcher kills himself after writing a confession of sorts, Dr. Maya Hansen, the other researcher on the project, calls her old friend Tony Stark for help. After a nearly antagonistic interview by an investigative reporter, Stark gets the call and jets off to Hansen’s aid. During a visit to a mutual friend that Stark had hoped would raise Hansen’s spirits, it becomes clear that the Extremis was used to transform a government-hating terrorist named Mallen into a killing machine. After Mallen unleashes his hate on a target to test his power, Stark decides that Iron Man must take him down.