Leo Fitz's History
Leopold James "Leo" Fitz is a former S.H.I.E.L.D. agent and scientist. A genius engineer, he is one of the youngest and most prominent members of S.H.I.E.L.D.'s Sci-Tech division, and inseparable from his research partner and friend (and later wife), Jemma Simmons. He, along with Simmons, was recruited to Coulson's Team and worked with them on all of their missions. While on the team, Fitz became good friends with Grant Ward and Skye. During the HYDRA Uprising, Fitz was an active participant in hunting for John Garrett and the rest of the Centipede Project. He was shocked by the revelation that Ward had been a member of HYDRA all along, and refused to believe it. When Ward was ordered to kill him and Simmons, they were trapped on the ocean floor. They escaped, but Fitz spent a long period of time without oxygen, causing brain damage.
As time progressed, Fitz's condition seemed to get better with help and support from his fellow S.H.I.E.L.D. colleagues rebuilding it. Slowly regaining his skills, Fitz was able to get back into doing active field and lab work, and played an important role in the conflicts with Robert Gonzales' S.H.I.E.L.D. faction and during the War against the Inhumans, in which he caused the death of Gordon. However, soon after the war was over, Simmons was swallowed by the Monolith and disappeared.
Fitz studied the Monolith for months and with S.H.I.E.L.D.'s help, he went through a portal to a distant planet and rescued her. Although Simmons returned, Fitz was devastated to learn she had met and bonded with the astronaut Will Daniels. Fitz helped Simmons research a way back to the planet, but their work attracted the attention of HYDRA, which forced Fitz go back to the planet to bring Hive back on Earth. There, Fitz learned that Daniels had died and his body was possessed by Hive. Fitz destroyed Daniels' body and returned home, believing the Inhuman was dead. However, the dark Inhuman, Hive, managed to return to Earth. Fitz and Simmons, having become a couple meantime, tried to find a cure to Hive's power of controlling Inhumans' minds. S.H.I.E.L.D. eventually managed to kill Hive.
S.H.I.E.L.D. had its new Director appointed by the president after the signing of the Sokovia Accords. Fitz worked with Dr. Holden Radcliffe on developing an Artificial Intelligence called Aida which was designed to serve S.H.I.E.L.D. as a decoy target. He was caught in an explosion with Phil Coulson and Ghost Rider by Eli Morrow and was almost sent into another dimension, but managed to get out. Fitz then helped S.H.I.E.L.D. in their last fight against Morrow. To Fitz's shock, Radcliffe betrayed S.H.I.E.L.D. and used Fitz's technology against S.H.I.E.L.D.. Fitz was captured and his mind was connected to the virtual reality called the Framework where he lived a rewritten life as The Doctor, Aida's lover and HYDRA's ruthless second-in-command. After he created for Aida a machine to become a real person, Fitz left the Framework, traumatized from his behavior there. But when Aida learned Fitz didn't love her back, she planned her revenge on him. S.H.I.E.L.D. eventually succeeded in defeating her. Shortly after, everyone in the team but Fitz were taken by mysterious people.
Fitz was then arrested by the army and taken to a black site prison. However, former S.H.I.E.L.D. agent Lance Hunter rescued him and brought him to Enoch, the one who took the team. Fitz decided to go into suspended animation for 74 years to facilitate his rescue of the team. Once in the future, Fitz took up the identity of Boshtok the wealthy Marauder. He managed to break Simmons and Daisy Johnson free from Kasius' enslavement, getting engaged with Simmons in the process. After the team managed to return to the present, however, due to multiple stressful factors, Fitz also experienced a psychic split which enabled his dark personality from the Framework to resurface at times. They continued working on a way to prevent the Destruction of Earth, came into a conflict with Hale's HYDRA cell and later with the Confederacy. In their final battle against Glenn Talbot they succeeded to change the course of history, however Fitz was killed in the process. However, due to the method he used to travel to the future, a younger version of Fitz remained alive, though cryogenically frozen in space.
