Extremis

Tony Stark, a renowned weapons designer, leads a mission in Afghanistan that goes wrong. He is gravely wounded by a bomb he helped design, and shrapnel lodges near his heart. He is captured by Afghan terrorist forces, and with Ho Yinsen's help he begins building a suit to escape, though Yinsen sacrifices himself in the escape.

Stark and Ho Yinsen, fellow captives, work to build a crude Iron Man suit inside the cave. The improvised armor enables their escape, but Yinsen sacrifices himself to buy Stark's freedom. Stark survives the escape with a new sense of responsibility.

In Texas, Mallen receives an Extremis injection that triggers a painful metamorphosis. The others who witness the scene are terrified as his body begins to mutate. The transformation hints at the dangerous potential of Extremis.

As the Extremis effects take hold, the injected man’s body becomes increasingly altered, his scar tissue thickening as he heals. The phenomenon escalates the threat posed to anyone nearby. The scene foreshadows violent power unleashed later.

In New York, Stark is stirred from dormancy by a routine interview reminder. He confronts regrets about arming the world with weapons and sees the Iron Man suit as a path to redeem himself. He cancels his plans, suits up again, and takes to the sky.

In Austin at Futurepharm, Aldrich Killian records a confession after destroying company records, admitting he released the Extremis serum for a larger purpose. Maya Hansen, a scientist from Stark's past, is alerted to these events and reaches out to Stark about Extremis. The stage is set for a confrontation with Stark.

Stark arrives in Texas during a high-stakes boardroom teleconference, resisting calls for his resignation. He argues Stark Industries can fund innovation without government support thanks to new phone technology. He orders his team to escalate the counter-extremis plan by sending Killian's hard drive to be hacked.

To keep Maya on board, Stark escorts her to meet his mentor, Sal Kennedy, in San Diego. The meeting grounds her in Stark's ongoing plans and the Extremis project.

The FBI field office becomes a target as Mallen's powers erupt into a public crisis. Maya reports the spread of Extremis to the media, raising public awareness and intensifying the threat. Authorities scramble to understand and contain the situation.

Stark rushes to Futurepharm to obtain the means to counter the Extremis threat. He uses non-lethal repulsors from his armor to halt a truck-tank pursuit of Mallen, but Mallen rebounds with even greater speed and strength, escalating the battle.

Iron Man is pushed to his limits as the fight tears through a shattered city. Stark endures devastating injuries while police crews lift a burning car off him and his suit struggles to keep pace. He ultimately leverages flame heat to power his suit at a critical moment.

After the threat is momentarily contained, Stark reveals his Iron Man identity to Maya in a private moment at Futurepharm. He notes the two-key security and hints at her possible accomplice role in the Extremis project. Maya accepts the consequences and defends Extremis by comparing it to weapons of mass destruction.

Stark responds with a quiet resolve to live with himself, stating that tomorrow he’ll be able to look in the mirror. The moment marks a turn toward a new path for Stark and for the Iron Man legacy.