X-Factor Investigations was a detective agency run by Jamie Madrox the Multiple Man. The initial staff consisted of Madrox's best friend, Guido Carosella (Strong Guy) and their former teammate Rahne Sinclair (Wolfsbane). The agency was originally named XXX Investigations, but the name was changed because Rahne thought that it sounded too much like Madrox was investigating pornography. The firm was renamed X-Factor Investigations after the government-sponsored X-Factor mutant superhero group that the three founders had previously served on.
Following M-Day, Madrox's new-found wealth (from winning a Who Wants to be a Millionaire-style game show) allowed him to recruit two of his former colleagues of the Paris branch of the now-defunct X-Corporation: Siryn and Generation X's Monet.
Rictor, who'd lost his powers on M-Day, was fighting severe depression and suicidal thoughts. When he was found by Jamie on the edge of a building ready to jump, Jamie sent one of his dupes to talk to Rictor. After chatting for some time, the dupe managed to get through to Rictor and he changed his mind about ending his life. However, as he was about to get away from the edge, the dupe pushed him, revealing his unstable personality. Luckily for Rictor, Monet St. Croix arrived at that exact instant and caught him mid-air. Afterwards, Rictor accepted Jamie's offer to join the detective agency.
Siryn, as part of her duties for X-Factor Investigations, investigated the murder of a woman who died in Jack Vaughn's penthouse under suspicious circumstances. Jack Vaughn (a movie star) claimed that the woman had been killed by her sister, Gloria Santiago, who was upset about the relationship between the two. Rival agency Singularity Investigations represented Jack Vaughn, with Damien Tryp, Jr. as the defense counsel, while X-Factor Investigations tried to help Gloria. After Monet established a mental bond with Gloria to assess the truth, she managed to incriminate Vaughn, while Layla Miller, a mysterious young girl, thwarted SI’s assassination attempt on Rictor. Tryp, Jr. was so infuriated by this that he badly beat Siryn and left her for dead (having shot her in the neck with a dart that prevented her from using her powers). She was then captured by Doctor Leery, but, with the help of Rictor, she escaped, getting Leery killed in the process.
Madrox and Strong Guy gave Tryp a very public warning as Tryp was jogging in Central Park. They told Tryp that they knew that it was him who hurt Siryn, and while they would not hurt him in broad daylight, he should watch his back. With this, Tryp, Jr. and Tryp, Sr. made Madrox an offer to merge X-Factor with their firm, which Madrox rejected.
After the meeting, Madrox started suspecting Singularity Investigations wasn't responsible for the decimation, as he'd previously thought, so he asked Siryn to find out more about it from the heroes who might have been involved (by using her modulated voice to make them more suggestible). She learned from Spider-Man, and later from Quiksilver, that the X-Men (who had denied any involvement) were, in fact, central to the ending of the House of M and the subsequent Decimation. After a confrontation, Madrox decided X-Factor would take a public stance in defiance of the Superhuman Registration Act and the X-Men decided not to interfere with Quicksilver as long as he stayed in Mutant Town.
A former Singularity employee went to X-Factor Investigations and revealed that Tryp was attempting to create a modern version of the Legacy Virus. Strong Guy was sent to drive the man to safety but once they were alone, Strong Guy killed him and called Tryp to report it. Guido tried to tell the team that the man had vanished on him but Wolfsbane smelled his blood on Guido's hands and a psychic scan by Monet revealed the truth. It seemed Tryp had placed a hypnotic suggestion in Strong Guy’s head to turn him into a sleeper agent. After breaking into Singularity Investigations, the elder Tryp confronted the team and revealed that all of Singularity Investigations' efforts to create the new virus had been made to prevent a possible future in which X-Factor managed to undo the Decimation and ended up causing humanity's destruction at the hands of re-powered mutants in a bloody conflict.
As the team was fleeing the building, one of Madrox's dupes blew up the whole thing, apparently killing Tryp, Jr. and Tryp, Sr. After this, the elder Damian Tryp, who had managed to survive the explosion, revealed to Layla that her very existence had foiled his plans, but things would be different now that he knew of her existence.
Next, several members of the team had their own solo adventures. While Jamie left on a trip to gather his lost dupes, Siryn and Monet bonded on a trip to France after finding out he (or a dupe) had slept with both on the same night. When they all got home, a group of ex-mutants believing the government had depowered mutants was now operating in Mutant Town. After Quicksilver restored most of the mutants' powers using his Terrigen Crystals, X-Factor, reinforced by a battalion of dupes, marched to face the group, but, in the end, it was their unstable powers that led to their defeat, resulting in the death of one of them and others' retreat. Quicksilver was dealt with by Rictor, who turned against him after he threatened Layla.
X-Factor tangled with The Isolationist, a powerful telepath (among other things), who convinced Madrox, Cyclops, and Beast to organize a "Million Mutant March" political rally on Washington, D.C. to get mutants declared an endangered species by the U.S. government. However, Layla Miller told Madrox that one of Huber's agents had tried to kill her, leading to a confrontation between Huber and the team, which resulted in Madrox, Guido and Rahne being teleported to a frozen wasteland. Luckily, Rictor and Monet fought Huber soon after and forced him to retreat, rescuing the team in the process.
Madrox, Rictor, and an accompanying Layla Miller were alerted to the Xavier Mansion by Emma Frost after the first mutant birth since M-Day. Madrox and Layla were sent to Forge's headquarters to send two dupes into different alternate realities. Layla jumped in with one of the dupes at the last minute, claiming she had a part to play in their mission. Unfortunately, Forge informed Madrox that there was no way to retrieve Layla and his dupes, who received instructions to kill themselves once they received the information they needed to get reabsorbed into Madrox Prime. Layla and the Madrox-dupe landed in Bishop's future, where they were captured and branded as mutants. After learning what they needed, Layla stole a grenade and killed Madrox's dupe, allowing the team in the present to become aware of their findings.
The end of Mutant Town
After Rahne's departure, Rictor decided to quit as well, but was kidnapped by the X-Men villain Arcade before he had the chance. In addition to that, Arcade also spread several bombs and placed a disintegration grid surrounding Mutant Town, preventing everyone from getting in or out. In the end, X-Factor managed to shut the grid down, but they were unable to save Mutant Town, as it was destroyed by Arcade's bombs.
In the aftermath of the event, Val Cooper met with the team and tried to recruit them, giving them 24 hours to think about it. Around this time, Madrox also began hallucinating a figure of Layla Miller, who would help him realize things that his subconscious already knew. Thanks to this, Madrox realized what Siryn had been trying to tell him for the last couple of days: she was pregnant with his child. After talking to her about it, the two embraced and discussed the future of the baby and Val Cooper's offer. The whole team then voted, but decided to escape and relocate to Detroit, Michigan.
Time in Detroit
Secretly, Val reached Jamie again, and X-Factor started taking cases for the government as well. After some of government cases, they took the case of Hector Muñoz, who was looking for his son, Darwin. Coincidentally, Darwin was in town, searching for Xavier with Longshot, secretly a skrull named Nogor the Talisman. There were some altercations with She-Hulk and her partner Jazinda, but "Longshot" was eventually revealed as an impostor and everyone joined forces to defeat Nogor.
Darwin was reunited with his father, only to be betrayed and sold out to operatives of an organization known as the Karma Project, who were experimenting on living human beings. Meanwhile, the real Longshot showed up to find out why there was a duplicate of him in Detroit and ended up being crucial to finding and saving Darwin.
Siryn also gave birth around that time and finally acknowledged that her father was dead. The baby was then named Sean, in his honor. As Jamie held his son for the first time, tragedy struck and he absorbed Sean, leaving Theresa in a deep state of sorrow.
Jamie also didn't deal well with the situation well and left X-Factor Investigations. In his absence, Terry became the leader of the team, despite not being in her best state of mind. X-Factor and new members Longshot and Darwin battled Cortex, the other dupe who had been sent to the future by Forge and grown resentful of Jamie after getting trapped in a vortex for millennia. Cortex briefly controlled Shatterstar and M, using them to respectively make assassination attempts on Rictor and Lenore Wilkinson. When Cortex lost control over Monet, she attacked him and his hood fell back revealing his identity. He tried to psychologically manipulate Monet and Syrin but they never hesitated to hit him with everything they had. In the end, he was teleported away before being able to kill his targets.
Back in New York
Not long afterwards, Jamie also came back and took Guido to open a new branch of XF in New York, allowing Terry to stay in charge in Detroit. This didn't last long though and soon she disbanded X-Factor and returned to her family's home in Ireland with Monet, who was hoping her friend would "recapture her soul". Still, Monet felt she wasn't getting better and decided to travel to New York and try to convince Madrox to pay Terry a visit. This visit would force Monet to face her own demons when she received the news that her father had been supposedly kidnapped by terrorists.
Once there, they reunited with Layla, who had been staying with Doctor Doom since her return from the future. They also learned that this Doom wasn't to blame for the kidnapping of Invisible Woman, that they were investigating. Apparently, an alternate version of him had been brought to their reality and was in New York about to kill Franklin and Valeria Richards. To stop him, X-Factor used another one of Shatterstar's portals to teleport back. While they were making the jump, Layla intentionally distracted Shatterstar at the exact moment that Strong Guy was punching the evil Doom, causing Shatterstar to abruptly close the portal and behead him, leaving himself and Layla behind.
Layla and Shatterstar were next seen at the Dublin Airport to save Theresa (now going by Banshee) from Trask's MRD. After her rescue, the trio returned to New York, alongside Monet and Strong Guy, who were also returning from her father's rescue operation. With X-Factor now at full force, they defeated Trask, and Terry and Madrox finally reconciled.
After an encounter with Bloodbath left Madrox temporarily dead, Havok and Polaris briefly took over the team on behalf of Wolverine, but this didn't last long as Jamie soon returned and Alex realized they had very different leadership styles, causing him to leave.
In a short span of time, X-Factor lost even more members. First, Guido fell out with Monet after a date gone bad. Later, while on a mission to fight an alternate version of Dormammu, Guido risked the life of a civillian, causing Monet to yell at him and call him a soulless monster. Guido got fed up and left X-Factor after being recruited by a mysterious figure.
The second to leave was Rahne. She had decided that she needed to find her son, Tier, to make up for abandoning him when he was born, and Rictor and Longshot helped her track him down. When they found him, however, they saw themselves forced to fight Darwin, who was hunting the child, and Vanora, making Rahne think that it was best to stay hidden with her son in order to protect him.
Then, almost concurrently, Polaris learned that she was the one that killed her birth mother and stepfather, making her more unstable than ever before. Terry, hoping to help her friend, asked Layla to help her contact the Morrigan in an attempt to save Lorna's sanity. After summoning her, she learned she had to kill the Morrigan and become the new Morrigan, so killed her using a "Banshee's scream" and, with her new godly powers, she easily saved Lorna. With this new responsibility however, she decided to leave the team behind, promising to return if they ever prayed to her.
Hell on Earth War
Rahne was the first of the former members to reunite with the team, but not under the most pleasant circumstances. With Darwin still hunting her son, she was forced back to New York with her son. They managed to get to X-Factor's HQ safe and sound, but were quickly followed by Darwin, and later by Jezebel and Strong Guy, all planning to kill Tier. Without much explanation, everyone present was then teleported before the Hell Lords, who were also waiting to kill him. Seeing that the war was no longer avoidable, Jezebel turned tides and helped X-Factor escape, soon explaining that she was only trying to try kill Tier before to prevent the Hell Lords from beginning their war for Tier's life, prophetized long ago to be the decisive conflict to define the true Hell Lord of the Universe.
They tried to lay low for a while, as Tier didn't want to charge to battle and he was the only one capable of killing the Hell Lords, but when Mephisto turned against the other Hell Lords and declared himself the new ruler of the Earth, X-Factor finally decided to take the fight to him.
Tier handled himself against Mephisto, but, to the surprise of everyone, he was instead killed by Guido, who was seeking the powers of the Hell Lords to revive a recently-deceased Monet. As he got his new powers, he ended the war and dispersed the members of X-Factor through time and space, successfully disbanding the team.
Following Aurora's disappearance, her twin brother Northstar requested the the Five to resurrect her. Since they could not confirm she was actually dead, they were not allowed to include her on Krakoan resurrection protocols. When Northstar was venting about his sister's supposed death at the Green Lagoon Tiki Bar, Polaris suggested him to create an investigative force tasked with solving mysterious mutant disappearances and/or deaths. Their plans were overheard by a drunken Daken who decided to join them.
When thinking about available and suitable collaborators to their new investigation team, Northstar and Polaris recruited Prodigy and Prestige. After Polaris shared their plans on a mutant social platform, the new team was also joined by Eye-Boy. The group's power sets and their combinations proved to be an efficient investigative method, solving Aurora's case. Since her death was confirmed, she could be resurrected.
Later that day, Polaris and Prodigy presented their actions to the Quiet Council, wishing to be sanctioned by the Krakoan authorities. Their request was supported by the Five. The Quiet Council approved the reformation of a new X-Factor Investigations, to be led by Northstar. Following the sanctioning of the team, Polaris then built a metallic tower on Krakoa to serve as X-Factor's headquarters.
Other mysterious deaths they investigated included Wind Dancer, who's death led them to discover a bunch of mutants trapped on Mojoworld, Rockslide, who couldn't be resurrected properly because he died in Otherworld, Siryn, who was forced to kill her over and over again by the Morrigan and Scarlet Witch, who asked Magneto to kill herself in order to complete a ritual to expand the capabilities of Krakoan resurrection.
- X-Factor Hearse (formerly)
- Shatterstar's Teleportations (formerly)
- X-Factor Hummer (formerly)
- 164 appearance(s) of X-Factor Investigations (Earth-616)
- 7 appearance(s) in handbook(s) of X-Factor Investigations (Earth-616)
- 2 minor appearance(s) of X-Factor Investigations (Earth-616)
- 27 mention(s) of X-Factor Investigations (Earth-616)
- 7 mention(s) in handbook(s) of X-Factor Investigations (Earth-616)
- 162 image(s) of X-Factor Investigations (Earth-616)
- 21 member(s) of X-Factor Investigations (Earth-616)
- 3 item(s) used/owned by X-Factor Investigations (Earth-616)