Doctor Danton Black was Professor Martin Stein's assistant during the development of the experimental Hudson Nuclear Power Plant. Shortly before the plant opened, Stein caught Danton stealing plant designs and fired him, but did not turn him in. To cover his tracks, Danton went to the authorities and concocted a story that Stein had stolen the plans for the plant from him.
The Nuclear Regulations Council decided to postpone the plant's opening while they investigated Danton's accusations. Stein, fearing that the delay would cause enough public concern to prevent the plant from ever opening, decided to turn the plant on to demonstrate that his theories were sound. His test, however, was sabotaged by ecoterrorists who placed a bomb in the facility. The resulting explosion caused the merger of Martin Stein and Ronnie Raymond into Firestorm. Ronnie and Stein weren't the only ones present at the plant, though. Danton Black snuck into the plant in hopes of finding more evidence to use to frame Stein and was caught in the explosion.
While Ronnie and Stein gained the power to fuse together, Danton gained the power to fission apart into multiple copies of himself, which he called his duploids. With this power, he became the super villain named Multiplex. The duploids, which shared his thoughts and identity, were sometimes carbon copies of himself but he could also create smaller duploids. Early in his career, he was forced to find an energy source to boost his powers. Later, he discovered his own energy source so he could, in theory, create unlimited duploids.
Multiplex was Firestorm's first super-powered enemy. He was primarily motivated by money, power and revenge. Multiplex was involved in the plot to kidnap Lorraine Reilly and perform experiments on her, which led to her becoming Firehawk. He also engineered an unsuccessful attempt to eliminate Firestorm by recruiting a handful of villains for the task.
Multiplex later joined the Suicide Squad, performing dangerous missions for the government in exchange for pardons for his crimes. The Squad was called upon to stop Firestorm, who threatened to dismantle the world's nuclear arms. During the confrontation, Parasite was mistakenly released. Parasite went on a rampage and appeared to have killed Multiplex by draining him first of his powers and then of his life.
As it turns out, though, stories of Danton's death were greatly exaggerated.
Years later, when Killer Frost discovered that Ronnie Raymond was inside of the new Firestorm, she contacted Firestorm's old foe, Cliff Carmichael, who quickly assembled a small team of villains to get their revenge on Firestorm. Multiplex was all too happen to join this team.Character Milestones