US Senator Robert Kelly is a major proponent of the Mutant Registration Act, a law that, if passed, will force mutant citizens to come forward and expose their identities. The bigoted senator is kidnapped by Magneto and his mutant terrorist group and taken to their island base where Magneto subjects Kelly to the power of his radiation machine which forcibly turns normal humans into mutants. Kelly is locked up in a cell but discovers that his mutation has made his body extremely soft and pliant, allowing him to squeeze through the bars of his cell. The senator plummets from the island rockface and into the ocean, making it to shore.
After returning to the US, Kelly seeks out the X-Men and turns up on the doorstep of the Xavier Institute. A medical examination determines that Kelly's body is rejecting the artificial mutation caused by Magneto's machine and his body starts to break down at the cellular level. Later, Storm stands at Kelly's bedside as he dies, his body liquefying and turning into water.