This character should not be confused with the Marvel hero named Deathlok.
Young S.H.I.E.L.D. recruit Jason Todd had a bright future with the international crime-fighting agency. He was personally mentored by both S.H.I.E.L.D. director Bruce Wayne and Moonwing (Dick Grayson). Although Todd was sometimes reckless, he was nonetheless chosen to become the new Moonwing when Dick Grayson temporarily left S.H.I.E.L.D. to attends Oxford University.
As the new Moonwing, Jason Todd made a careless mistake that resulted in the death of another S.H.I.E.L.D. agent. Summarily dismissed from the ranks of S.H.I.E.L.D., Jason Todd became furious with his mentors and blamed them for his disgrace. Soon after, Jason Todd was caught in an explosion when the psychotic villain known as Hyena (Creed H. Quinn) detonated a bomb in an attempt to kill Bruce Wayne and Dark Claw (Logan Wayne). Although his body was never recovered, S.H.I.E.L.D. presumed that Jason Todd died in the bomb blast.
But Jason Todd survived, barely. He was left broken and gasping for life under the rubble of a building. His body was recovered by agents of the criminal organization known as HYDRA and his damaged body parts were replaced with robotic parts, transforming Jason Todd into the cyborg known as Deathlok. As Deathlok, Jason Todd became an agent of HYDRA.
Inside the Green Skull's Hydra Base Supreme, Deathlok participated in a coup led by Madame Cat (Selina Luthor) to overthrow Lex Luthor as Supreme Hydra. Deathlok looked on as Madame Cat seemingly killed her father by strangling him with her whip and then pledged allegiance to her as the new Supreme Hydra.
Later, as S.H.I.E.L.D. agents attempted to launch a ground assault against Hydra Base Omega, Deathlok was one of Hydra's agents sent to engage the invading forces. On the battlefield, Deathlok soon spotted his former mentor Moonwing (Dick Grayson) and attacked him from behind. Deathlok revealed he had been waiting a long time to destroy both Dick Grayson and Bruce Wayne. Unmasking Moonwing, Deathlok accused Grayson and Wayne for abandoning him. Using his superhuman strength, Deathlok began to strangle Moonwing because he wanted to see Dick Grayson broken and gasping (just as Todd was left after the Hyena's bomb exploded). But before Deathlok was able to kill Moonwing, Colonel Nick Fury and Sergeant Joe Rock commandeered an aircraft and shot Deathlok several times in the back. Although he felt sorry for Jason Todd, Dick Grayson once again left him for dead so that he could continue the assault on Hydra Base Omega.
Marvel's Agents of S.H.I.E.L.D.
A character named Mike Peterson, who later gets the name of Deathlok, appears in the Marvel Cinematic Universe series Marvel's Agents of S.H.I.E.L.D., played by J. August Richards. He starts out as a good guy, but later becomes the quinary antagonist of season 1. He appears in the pilot episode as a superhuman factory worker who saves a woman from an exploding building (being destroyed because of a Centipede Group experiment going wrong) with superhuman strength and jumping. Approached by eventual protagonist of the series Skye in a cafe, she warns him that S.H.I.E.L.D. might be after him soon for revealing himself as superhuman publicly. He has a conversation with Raina, a representative from the Centipede Group, where Raina doesn't seem too happy for risking the exposure of the Centipede Group's existence and plans. The next day, Mike tries convincing his boss to give him a chance to get his job back, but he refuses.
Mike gets furious and straight-up murders the factory owner, prompting Phil Coulson from S.H.I.E.L.D. to go after him. He is shot in the head with an I.C.E.R. gun by Grant Ward, then goes off to a S.H.I.E.L.D. training facility to hopefully make up for killing the factory owner. He joins up with Coulson to go after some guys using the Centipede serum that gave Mike his powers, and is seemingly blown to pieces saving his son Ace from Raina. He wakes up in a room that looks like it's from a Saw movie and has most of his body burned. A robot eye implant shows him computer text of the Clairvoyant telling him to "await further orders".
Later, he is given a robot leg by Ian Quinn, which (painfully) attaches itself to Mike's destroyed leg, making him Deathlok. He later attacks Garrett at Cybertek in the episode "Beginning of the End".