HEAD CASE
Real Name: Sean Madigan
Identity/Class: Human mutate
Occupation: Lab technician, terrorist
Group Membership: A.I.M.
Affiliations: Agent Baines, Doomsday Man, Kerwin Korman, Targoth
Enemies: Araña (Anya Corazón), Lightning Storm (Agent Baines, Agent Locke, Agent Sum, others), Ms. Marvel (Carol Danvers), M.O.D.O.K. (George Tarleton), Monica Rappaccini, S.H.I.E.L.D., Wonder Man (Simon Williams)
Known Relatives: George Tarleton (father), Linda Madigan (mother), Alvin Tarleton (paternal grandfather)
Aliases: A.I.M. Technician 4591, Black Skull (rejected codename)
Base of Operations: A secret A.I.M. laboratory;
formerly an office in Seattle, Washington;
formerly A.I.M. Sub Base #94 accessed from a warehouse
on North End of New York City
First Appearance: Ms. Marvel II#11 (March, 2007)
Powers/Abilities: Sean Madigan possessed some kind of science degree that made him capable of working for A.I.M., but we don't know his actual field of expertise. He was physically an average guy, knew how to fire energy weapon and understood some of A.I.M.'s advanced technology enough to hack, manipulate or combine whatever device he got his hands on. He was very manipulative and cunning and was driven by his desire for vengeance against his biological father. He had bad eyesight and had to wear glasses.
After his transformation into Head Case he had the power to...we don't know until he appears again. He was good at sitting and glowing as far as we know.
Height: Unrevealed (5'6"; by approximation)
Weight: Unrevealed (150 lbs; by approximation)
Eyes: Brown
Hair: Brown (changed from blond to brown throughout the
storyline)
History:
(Ms. Marvel II#17 (fb)) - Linda Madigan had an affair in college with
George Tarleton. He abandoned her when she told him that she was
pregnant.
(Ms. Marvel II#17 (fb) - BTS) - Future S.H.I.E.L.D. agent Baines and future A.I.M. agent Madigan were part of the same social uber-geek circle. Madigan made a deal with Baines and helped him out when Baines ran into financial issues due to his father's losing battle with cancer.
(Ms. Marevl II#11 (fb) - BTS) - During his first six months with A.I.M., Madigan made it to A.I.M. Sub Base #94 300 feet below Manhattan where Doomsday Man had been in storage among other things like the Targoth. He liked visiting Doomsday Man and one heard him screaming about killing Ms. Marvel. (take some of this information with a grain of salt because he was lying through his teeth to Ms. Marvel at the time)
(Ms. Marvel II#16 (fb) - BTS) - At some point Monica Rappaccini had a fling with Sean Madigan.
(Ms. Marvel II#12 - BTS) - Madigan secretly gave Korman control over the Doomsday Man. (see comments)
(Ms. Marvel II#11) - Madigan fled the Sub Base and went to Ms. Marvel's home, but got knocked out by Araña, who saw him sneaking around Carol's balcony. Carol took off his suit's mask and handed it to Araña, who learned Sean Madigan's name from it. Madigan regained consciousness shortly after and revealed to Carol that Doomsday Man was awake. He gave her an update on how A.I.M. had collected Doomsday Man and Korman from a hospital after his battle against the Avengers and had ever since tried to figure out how the man and the robot had become fused and evolved. He told her about his last visit to Doomsday Man at the Sub Base and how he seemed to be dreaming about killing Ms. Marvel. Doomsday Man awakened shortly after and began to run rampant throughout the facility where even more dangerous things were stored. He told Ms. Marvel the location of the facility before teleporting away. (Madigan was not telling the complete truth about his last visit to Doomsday Man)
(Ms. Marvel II#12) - In A.I.M. Bunker #99 Madigan had to defend himself in front of a council of higher A.I.M. operatives for Doomsday Man's failure against Ms. Marvel, who was only supposed to be a test run for the Korman-controlled robot. Madigan laid the blame on Korman for failing to operate the robot properly. They threatened him, but Madigan revealed that they had to keep dealing with him if they wanted to kill M.O.D.O.K. because he had accessed the deepest parts of the A.I.M. network through Korman and knew were M.O.D.O.K. currently was. The A.I.M. higher ups wanted to know more, but it would have a price for them.
(Ms. Marvel II#16 (fb) - BTS) - Madigan brought together the six remaining leaders of the warring A.I.M. factions with promises of aiding them in their goals. They all sought to get rid of M.O.D.O.K. and take control over the whole organization and Madigan made them promises to help them.
(Ms. Marvel II#17 (fb) - BTS) - Madigan finally called in the favor S.H.I.E.L.D. agent Baines owed him and Baines became his mole within S.H.I.E.L.D.'s Lightning Storm strike team.
(Ms. Marvel II#17 (fb) - BTS) - At some point Madigan gave Baines a psychic scrambler to hide his traitorous intentions from S.H.I.E.L.D.'s psi-operatives, including his fellow Lightning Storm operative Locke.
(Ms. Marvel II#15) - Madigan infiltrated M.O.D.O.K.'s portion of A.I.M. and quickly gained M.O.D.O.K.'s trust. He learned that M.O.D.O.K.'s body was breaking down as a late side effect of the experiment that had mutated him and that he needed the G-TAC Scrambler, a DNA bomb, to correct his physical degeneration.
(Ms. Marvel II#15) - Two A.I.M. agents found and picked up the G-TAC Scrambler at the regional A.I.M. headquarter in Anderson, Indiana after killing two S.H.I.E.L.D. agents that were guarding the base after a recent battle. Madigan teleported in and confronted his A.I.M. colleagues before they could reach their van. He addressed Joe's wish to rather die quickly than get his DNA scrambled by the G-TAC by killing both of them with two energy guns.
(Ms. Marvel II#15 - BTS) - Madigan stole the G-TAC Scrambler.
(Ms. Marvel II#15) - Madigan was at M.O.D.O.K.'s side at A.I.M. Research Base Alpha while M.O.D.O.K. angrily pushed an A.I.M. agent down into the pit of the Gnashers, genetically modified gorillas, because he deemed the whole project a waste of resources. The agent was eaten by the Gnashers in the process and M.O.D.O.K. made it clear that all agents involved should be thrown into the pit. Madigan sent away everyone when M.O.D.O.K. vomited and claimed that M.O.D.O.K. was angered and that they should be thankful he didn't kill them. M.O.D.O.K. thanked Madigan for hiding his disease and asked for an update on acquiring the G-TAC Scrambler. Madigan claimed that it had been located and the agents were returning to base, but he had not heard from them since. M.O.D.O.K. confirmed to Madigan that the disease was spreading and Madigan claimed that they would find a cure. After M.O.D.O.K. went to sleep, Madigan teleported to Conference Room A in an office building in Seattle, Washington where the six A.I.M. leaders that sought M.O.D.O.K.'s demise were meeting. Madigan told them that he was preparing to reach the goal they sought and that they would all soon have to fight for their part of A.I.M. the same way Monica Rappaccini would have to. He had taken the G-TAC Scrambler to them, being fully aware that Monica, M.O.D.O.K. and Ms. Marvel's Lightning Storm squad had all found a way to track it down (M.O.D.O.K. had received the location from S.H.I.E.L.D. agent Baines, who had been ordered so by Madigan). He explained to his erstwhile allies why each party involved wanted the G-TAC Scrambler and then revealed that he wanted to re-create A.I.M. as dozens of autonomous cells instead of the mismanaged organization it currently was, which was not what the six men wanted. Madigan took a seat on the G-TAC Scrambler and gleefully told the six power-hungry men that the other parties would arrive shortly. Seconds later chaos erupted with squads serving Monica Rappaccini and M.O.D.O.K. teleporting in, as well as Ms. Marvel, Wonder Man and the former's Lightning Storm team crashing through window. M.O.D.O.K. teleported in by himself moments later and telepthically took control over Wonder Man.
(Ms. Marvel II#16) - Madigan stayed out of the battle, cowering on the ground while hugging the bomb. Lightning Storm's Agent Sum and Agent Locke noticed him while fighting the different factions. Agent Locke finally asked Agent Baines, their technical support aboard the Minicarrier, to lock down all A.I.M. teleporting after M.O.D.O.K.'s faction teleported in two Gnashers. Madigan fled the conference room with the G-TAC Scrambler, but Monica teleported in and had him at gunpoint. Madigan tried to teleport away, but it wasn't working due to Agent Baines blocking all teleportation. M.O.D.O.K. crashed through the wall to confront Monica, but suddenly...
(Ms. Marvel II#16 / Ms. Marvel II#17 (fb) - BTS) - ...S.H.I.E.L.D. Agent Baines, Madigan's mole within Lightning Storm, deactivated the teleportation lockdown for a three-second window to allow Madigan to teleport out with M.O.D.O.K. and the bomb.
(Ms. Marvel II#16 - BTS) - Monica was caught by S.H.I.E.L.D. and while in captivity alluded to Ms. Marvel that someone had deactivated the teleportation lockdown for Madigan to escape with M.O.D.O.K. and the G-TAC Scrambler because there was no way that Madigan found a way by himself according to her. Ms. Marvel was now aware that there was a traitor on her team working for Madigan. Monica also revealed that Madigan was M.O.D.O.K.'s son, which was the only reason Monica had shown any interest in him, and that Madigan planned to break apart A.I.M. into numerous factions.
(Ms. Marvel II#16) - M.O.D.O.K. was unconscious after he was teleported, but Madigan was surprised that his father had even survived the battle at all. Madigan cracked open his father's flying Doomsday Chair and connected the G-TAC Scrambler to it to power the bomb. Madigan sought to get A.I.M. on the front page of the news by detonating the G-TAC Scrambler in the most public spot possible. He then teleported M.O.D.O.K. to Times Square with the G-TAC Scrambler inside his Doomsday Chair.
(Ms. Marvel II#17) - Madigan filmed a statement to explain his history with M.O.D.O.K. to explain why he, M.O.D.O.K.'s rejected son, teleported him to the middle of New York City with the G-TAC Scrambler.
(Ms. Marvel II#17 - BTS) - Monica Rappaccini confronted Baines while Ms. Marvel and the rest of her team were off the Minicarrier. She knew that he was Madigan's mole and didn't even give him a chance to call S.H.I.E.L.D. command or defend his actions before knocking him over the head and shooting him with his own gun.
(Ms. Marvel II#17) - After the G-TAC Scrambler's activation on Times Square, Madigan began a live broadcast to every A.I.M. computer network across the globe and their outposts in realities 1610, 295 and 311. He declared M.O.D.O.K.'s control over A.I.M. to be over after the attack on Times Square, which he blamed on M.O.D.O.K. and then suggested that the only hope for A.I.M. to succeed in remaking the world was to split apart and work as separate cells that trusted nobody else that wasn't closely with them. He was still live when Monica teleported in and shot him straight in the head.
(Ms. Marvel II#17 - BTS) - Monica escaped after killing Madigan and took control over a quarter of A.I.M. while other factions got engulfed by paranoia and infighting.
(Ms. Marvel II#17) - Madigan's corpse was taken to a secret A.I.M. laboratory that specialized in reanimating the dead. Two A.I.M. scientist combined the knowledge they had gained from Doomsday Man's neural link to Korman and the reanimative properties of the Targoth virus to attempt the resurrection of Madigan. One of them wasn't so sure that Madigan would be happy with becoming an experiment, but the other one believed that he would. They placed Madigan inside a special suit, put an M.G. chip inside his skull, activated it, filled the suit with gel and placed a helmet on his skull. They argued over a codename for Madigan and decided he would be known as Head Case from now on.
Comments: Created by Bill Rosemann & Guy Davis.
Madigan was not one of the A.I.M. technicians seen at the beginning of Ms. Marvel II#11. Neither of them wore glasses and the masks weren't the same either. Madigan was probably already gone when one of them found Doomsday Man screaming. The presumed timeline of these events for Madigan probably goes like this: Madigan went to the storage facility where Doomsday Man was kept. Madigan gave Korman control over Doomsday Man and left a Trojan Horse in his software so that he was able to see whatever Korman was doing. Madigan then witnessed Korman begin dreaming about killing Ms. Marvel because he was in control at that point. Then Madigan probably left while Doomsday Man and Korman needed a bit more time to finally activate and then run rampant through the Sub Base.
Head Case appeared next in...nowhere. He received an interesting new look and then just never appeared again. The next issue began a storyline featuring Puppet Master as the bad guy. Maybe his resurrection was actually a failure and he was nothing more than a big, cool looking paperweight in the end...or we will see his actual return at some point in the future.
Earth-616's A.I.M. outposts Madigan contacted in other realities included 1610 (Ultimate Universe), 295 (Age of Apocalypse) and 311 (1602). Interesting fact!
This profile was completed on 08/30/2026, but its publication was delayed as it was intended for the Appendix 25th anniversary event.
Profile by Markus Raymond.
CLARIFICATIONS:
Head Case (Sean Madigan) has no known connections to:
images:
Ms. Marvel II#17, p23 (main, Head Case)
Ms. Marvel II#11, p18, pan2 (head shot)
Ms. Marvel II#11, p14, pan1 (full A.I.M. technician uniform)
Ms. Marvel II#15, p2, pan6 (firing energy weapons)
Ms. Marvel II#15, p16, pan5 (teleporting while in full A.I.M. suit)
Ms. Marvel II#17, p14, pan6 (takes a bullet to the head...)
Ms. Marvel II#17, p14, pan7 (...and ends up dead)
Appearances:
Ms. Marvel II#11 (March, 2007) - Brian Reed (writer), Roberto de la
Torre (pencils), Jon Sibal (inks), Bill Rosemann with Warren Simons
(editors)
Ms. Marvel II#12 (April, 2007) - Brian Reed (writer), Roberto de la
Torre & Patrick Zircher (pencils), Jon Sibal (inks), Bill Rosemann
(editor)
Ms. Marvel II#15-17 (July-September, 2007) - Brian Reed (writer), Aaron
Lopresti (pencils), Matt Ryan (inks), Bill Rosemann (editor)
First Posted: 09/06/2026
Last updated: 08/30/2026
Any Additions/Corrections? please let me know.
Non-Marvel
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