Dr. Maya Hansen was a brilliant scientist working for the FuturePharm Corporation in Austin, Texas alongside Dr. Aldrich Killian. Together they developed Extremis, an attempt to create a new super soldier. The Extremis is a techno organic virus that completely rewrites the body’s genetic code. It replaces entire organs making them more efficient. The virus also gives the body a sort of healing factor. The original Extremis grants super human strength, speed, endurance, reflexes and the ability to project electricity and breathe fire.
When the samples were stolen and given to domestic terrorists, Maya contacted Tony Stark, with whom she had studied with in college. Later it is revealed that she was the one who let the samples go. After a brief period in jail, Tony broke her free just to fix his brain. Later she was paroled and worked under Tony at S.H.I.E.L.D.
Years later, she was kidnapped by A.I.M., who forced her to recreate the Extremis virus in order to create their own super humans, when she tried to escape, she was killed by one of A.I.M.'s, now superpowered, agents. A failsafe plan she had if this happened was put in march few moments before her death, alerting Tony about the Extremis being on the loose once more.