Generator Gawl(1998)

Generator Gawl is a 1998 anime series set in 2007, when Professor Takuma Nekasa discovers a gene code that could unlock humanity's greatest mystery—and unleash its worst threat. Three young scientists from the future, Gawl, Koji, and Ryo, travel back in time to prevent the discovery. They arrive three months before the catastrophe unfolds, but face fierce opposition from Ryuko Saito, a brilliant scientist who wants the future to remain unchanged. Saito commands the Generators, inhuman assassins disguised as humans, to stop them at any cost. As Koji and Ryo race to complete their mission, Gawl must embrace his own transformation, becoming like his enemies to fight them on equal ground. The series blends time-travel intrigue with high-stakes genetic warfare.