Appeared in Iron Man 3
Agents of S.H.I.E.L.D.

Extremis was developed by Aldrich Killian and Maya Hansen in an attempt to recreate the Super Soldier Serum. Extremis rewrites the operating system of the human body, upgrading strength, speed and durability to the very zenith of human possibility.


Iron Man 3

Dr. Maya Hansen was a research scientist working on a revolutionary process to rewrite genetic codes when she attended a New Year's Eve party in Bern, Switzerland, where she met the rising star inventor Tony Stark. The process could fasten growth and enhance healing, but had the side-effect of causing spontaneous combustions on unstable subjects. Stark left her an equation that could supposedly fix the problems in the formula, but were not fully successful.

After Hansen joined forces with Aldrich Killian and his A.I.M. company, she brought her research with her and eventually the development of her Extremis virus led to her leading a 40-strong team of A.I.M scientists. The downside of Extremis was its explosively unstable nature. Some hosts would accept it, and remain somewhat stable with regular infusions and treatment, while some exploded violently. When Extremis was tested on human subjects a number of them went critical in public, causing Killian to invent a terror plot cover story to keep A.I.M.'s involvement a secret.

Years later, Killian visited the CEO of Stark Industries, Pepper Potts and offered her to join A.I.M., as they were developing the Extremis virus, but she declined.

It is revealed Killian was using the Extremis' instability to create human bombs for the terrorist the Mandarin, and had injected it to himself and his soldiers, including Eric Savin and Ellen Brandt.

Killian later kidnapped Pepper Potts in order to have an incentive for Tony to finally find the solution for the instability he started years ago, as Pepper was injected with the virus.

Pepper was later taken to the same place Killian was going to execute President Ellis, so he could have her as a trophy. Tony escaped captivity and managed to get to Pepper with the help of Jim Rhodes. During a battle against Killian, Potts was apparently killed. But she survived thanks to the regenerative properties of Extremis and managed to kill Killian. Tony promised Pepper he would find a cure for Extremis, which he did.

Agents of S.H.I.E.L.D.


Michael Peterson, a man living in Los Angeles, was seen rescuing a doctor from a burning building, and labeled as "the Hooded Hero". Peterson's background is that he was a factory worker who sustained an injury and was injected with an experimental serum at a lab operated by the sinister Centipede Group. S.H.I.E.L.D. scientists Leo Fitz and Jemma Simmons identify the Centipede Serum as a combination of alien metal, gamma radiation, a serum similar to Dr. Erskine's super soldier serum, and its principal component as Extremis. After breaking down and injuring his boss, Peterson abducted a hacker named Skye to tell his story and attempted to flee Los Angeles with his son Ace. Peterson was about to destroy the train station until he was tracked by S.H.I.E.L.D. agents led by Phil Coulson and a Project Centipede operative. Michael was sedated by Grant Ward while the Project Centipede operative sent by Debbie was defeated by Melinda May.

"Girl In The Flower Dress"

Project Centipede's Hong Kong branch and its operative Raina targeted the street performer Chan Ho Yin to find out how he got his pyrokinetic powers while finding a way to improve the Centipede Serum. They experimented on him by injecting him with the Extremis serum, which enhanced his pyrokinetic powers. Raina and Debbie (who previously worked on Michael Peterson) eventually extract most of his blood platelets to further their experiments. When S.H.I.E.L.D. raided the facility, Chan broke free, taking the name "Scorch", and reinjected the blood platelets into himself, killing S.H.I.E.L.D. Agent Quan Chen, fighting Phil Coulson and Melinda May, and incinerating Debbie while Raina escaped. After Melinda May killed Scorch by injecting an overdose of Extremis into his body making him explode, Agent Grant Ward stated that Skye had hacked the mainframe but was unsure if they would find the masterminds behind Project Centipede. Raina later visited a mysterious individual in an unknown prison and told him about what happened at China's Project Centipede facility and that they found a way to keep the unstable elements of Extremis from combusting. Raina also asked the person to have a word with "the Clairvoyant" about putting Project Centipede into Stage 3.

"The Bridge"

Coulson recruits Mike Peterson to his team for super soldier support when Edison Po is sprung from prison by upgraded Centipede super soldiers. Coulson's team traces a Centipede-powered soldier to an abandoned factory and are ambushed by a squad of super soldiers, who were subjected to the same eye implant as Akela Amador. Edison recommends to Raina to stop enquiring after the Clairvoyant or it could mean her death. Meanwhile, Coulson and May are keeping information regarding Skye's parents from her. When Peterson contacts his son, he learns that he has been kidnapped by Centipede, who suggest a trade Peterson for Ace. Coulson escorts Peterson to the arranged exchange, where Peterson reveals that Centipede want Coulson, not Peterson, for Ace. Coulson, agrees to be taken prisoner. After the exchange, Peterson attempts to rescue Coulson, but is apparently killed in an explosion. Raina tells Coulson that they want to know how he was resurrected.

Known users

Extremis effects on its subjects

As well as super strength and enhanced agility and reflexes, the user of Extremis is granted incrediblely fast regenerative abilities, being able to regrow whole limbs in seconds, and project massive amounts of heat from their skin, enough to melt metal. It also granted the users supernatural durability, with several Extremis users shown only taking minor damage from low caliber firearms.

An unfortunate side-effect is if someone injects too much Extremis, or their body rejects it, they will explode in a blast of heat measuring 3000 degrees Celsius, vaporizing anyone around them.

Aldrich Killian was able to channel the heat and breathe fire.


No obvious cure exists for Extremis but some treatments are possible; for example, the stun weapon developed by Leo Fitz and Jemma Simmons used on Michael Peterson when the "Centipede" Extremis was about to destroy him provided a "shock treatmet" which rendered the virus' instability inert, but did allow the enhanced abilities (such as super strength, stamina etc.) to remain. The Centipede Group managed to correct the instability in its test subjects using the flame and heat-resistant blood platelets taken from Chan Ho Yin.

It is left ambiguous, but it is possible that Tony Stark manipulated the equation developed by Maya Hansen and himself to send Extremis into dormancy in one's genetic code in order to "remove" the virus from Virginia Potts, effectively "curing" the affliction.


  • The origin and armor of Iron Man used in the 2008 film closely resemble those introduced in "Extremis". Based on his work on "Extremis", artist Adi Granov was brought on as a producer for the film, and he created the final designs for Iron Man's armor.
  • In the comics version of the virus, it can grant the user a variety of powers (most not heat-related) depending on how it is programmed and modified, and did not have the volatile instability of the movie version.
  • In the "Girl in the Flower Dress" episode of "Agents of S.H.I.E.L.D.," the character is portrayed by stunt performer Alvin Chon.


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