[4] A mutant with the ability to create instant duplicates of himself, Madrox was mainly a minor or supporting character until his appearance in the 1987 miniseries Fallen Angels.

[citation needed] He and the other members of his detective agency later starred in a revamped X-Factor monthly series that was again written by Peter David.

[citation needed] In 2018 he was featured in a second five-part solo series called Multiple Man written by Matthew Rosenberg and drawn by Andy MacDonald.

[9] Jamie Madrox is born to a family living near the Los Alamos research facility in New Mexico; the background radiation may have stimulated his mutation.

Professor Charles Xavier, a friend of the Madrox family, suggests that they move to Kansas to raise the boy in privacy.

Dr. Daniel Madrox, Jamie's father, creates a suit for him to wear which is designed to absorb kinetic energy, the source of the duplication.

He contacts Professor Xavier,[10] who sends the youth to Muir Island with Moira McTaggert, to work in her laboratory and help her with research.

[19] This becomes clearer to him when a duplicate, working for Mister Sinister, decides that it wants to absorb the original, which it does for a short time, until Jamie's dominant personality breaks free and reabsorbs the wayward dupe.

An attempted cure by Haven leaves him dead,[25] until it is revealed that it was a duplicate who had been infected and died; the real Madrox was alive and suffering from amnesia.

Banshee hires ex-criminals to police other mutants but things get bad when Mystique goes on a murderous rampage and has Mastermind's daughter mind control them.

[30] After the fall of the X-Corporation, Jamie Madrox begins working as a private detective in the "Mutant Town" area of New York, along with former X-Factor teammates Wolfsbane and Strong Guy.

By this point, his powers are developed to such an extent that any dupe who gains sufficient skills can pass its knowledge on to Jamie, giving him a wide variety of training instantly.

[33] Following the elimination of all but a couple of hundred mutants from the face of the Earth in the "House of M" storyline,[34] it is revealed that Jamie Madrox has upgraded his private detective agency to a new building, under the name X-Factor Investigations.

[36] Later, Layla Miller, without a home after House of M's reality is shattered, reveals to Jamie that one day they will get married, and Wolfsbane will kill them both on their wedding night.

[39] During the 2007 - 2008 "Messiah Complex" storyline, Cyclops sends Jamie Madrox and Layla Miller to go see Forge having built a machine that allows to monitor alternate timelines.

Layla and one Madrox duplicate arrive eighty years in the negative future to discover that the mutant race has been severely decimated.

There, they encounter a youthful Lucas Bishop that would gladly go back in time to kill the mutant baby responsible for the way this timeline has turned out.

Layla straps a stolen grenade to the duplicate, killing him and sending his memories of the event back to Jamie so he can tell of Bishop's treachery.

Jamie reveals that he plans to kill himself over the grief caused by Sean, but is prevented by a holographic projection of an adult Layla Miller who takes him into the future.

[volume & issue needed] After kissing Layla (now an adult) out of happiness at seeing her, Cyclops wants Jamie to find out why some mutants are winking out of existence.

[volume & issue needed] When Cortex loses control over Monet, he is attacked and his hood falls back revealing that he is a duplicate of Madrox.

Having his identity uncovered Cortex reveals himself as the second duplicate sent to one of the two "remaining" futures for mutantkind during the "Messiah Complex", to search for a cure for the depowering of 98% of the world's mutants following M-Day, then die in some fashion so that his memories would be transferred back to Madrox.

He was then sent back in time from Earth-1191 to Earth-616 to kill a list of specific individuals, including Multiple Man, for fear how they might affect the future.

[volume & issue needed] During the 2010 "Chaos War" storyline, Multiple Man is among the heroes that Hercules assembles to help combat the forces of Amatsu-Mikaboshi.

[volume & issue needed] The X-Factor team then discover that Deathlok, Rahne's daughter, and Dormammu have been transported to Madrox's home Earth as well.

This dupe is revealed to embody the treacherous aspects of the original Madrox and deliberately locked himself up for several years to find a way to become the new Jamie Prime.

The dupes from the Resistance are sent into the timestream to find help from a heroic-time traveling Madrox, who is revealed to be the Emperor from the further in the future who had a change of heart.

[citation needed] Jamie was formerly unable to control the duplication process, wearing a special shock-absorbent synthetic stretch fabric costume that contained mechanisms that absorbed kinetic energy so that an army of Madroxes would not instantly appear every time he was struck.

[58] In X-Factor, Damian Tryp declares Madrox is not a mutant, but a "killcrop" like him, so named because they were believed to cause bad harvests in olden times.

This version was captured and experimented on by Mister Sinister and the Dark Beast, who force his clones into serving him and leaving the original a childlike lunatic who is held at the Church of the Madri in Quebec.