In a world where steel monsters called 'Aberrations' are Earth's enemy number one, 'Arbiters,' or as many call 'magical girls' boast strength where even nuclear weaponry fails. Humanity's beacon of hope lies in the center of a military facility where a skeleton crew of mad scientists work around the clock on whatever freak experiments suit their contractor's whims.

In the last resort to isolate and preserve the Arbiters' powers before its too late, secret agent Helena Slater is the only washed-up layabout for the job.