The history of Mastermind is quite sketchy. No one really knows exactly who her mother was, but her father is the criminal genius and X-Man villian Jason Wyngarde, the original Mastermind. After Wyngarde's death at Muir Island due to his infection with the Legacy Virus, Martinique Jason appeared in his place. In her father's death, Martinique took the name Mastermind and has carried out her father's twisted tradition of creating illusions. Although Mastermind has the same power as her father Jason, she is also a novice telepath. She uses her telepathy to glean information from her victims to make the illusions even more realistic.
Martinique was hired by Arcade to frame Wolverine for some serial murders in London, one of the victims being Alexandra Davies, a friend of Gambit's years before. Gambit flew out to London to investigate her murder, and was led right to Wolverine, who had somehow been brought to London unawares. The two almost killed each other during Martinique's mental manipulations, but eventually realized that Logan was innocent and was being framed by Mastermind. While Martinique and Arcade were psi-linked, Mastermind observed something in Arcade's mind that she found disturbing. Very suspicious, Martinique forced Arcade to tell her the real reason she was there. She noted that Miss Locke and Arcade had been playing one of Arcade's favorite games and his beloved Locke had gone too far by cutting his face. After, Arcade choked Miss Locke to death. He had called Mastermind in because he had convinced himself that Wolverine had murdered his partner, and he wanted revenge. Martinique was disgusted at having been used in this horrible charade and implanted a recurring waking nightmare in Arcade's mind in which he's the elevator conductor in an hotel full of Miss Lockes. Martinique then disappeared into the shadows.
Martinique had poped up in Midtown Manhattan, terrorising Foggy Nelson, a friend of Daredevil. Attempting to lead Foggy to Arcade's abondoned Murderworld, Daredevil hanging outside, overheard everything that the two had been discussing. Daredevil made a trip to Mastermind's new hideout and found it quite frightening...Martinique had made everything look like Daredevil's old foes and she replayed the tragic death of his beloved Elektra. Appearing to him and Foggy as Mastermind, she told them that she only used Foggy to evaluate the equiptment in Murderworld, claiming that everything was now hers. Once again, Mastermind mysteriously disappeared.
Blob, Avalanche and Post attempted to attack Robert Kelly, who was being guarded by Nathan Summers, better known as the mutant Cable. The members of the Brotherhood of Mutants attacked Cable, and the hidden Mastermind cast the illusion that Brotherhood was defeated. Pyro, in the corner, screeched out the name "Mastermind" with the remaining strength he had within him, which enabled Cable to figure that she had been deceiving him. Mastermind was knocked unconscious by Cable's psimitar and Pyro shot Post. The blast was too powerful for him to handle, so with his last dying breath, he asked Kelly to finally end human and mutant war. Kelly agreed and promised to do so.
