Many people are born with unique abilities that aren't powerful enough to have any superhuman use. Experiments are held to take people with ineffective powers and improve them, instead of creating a superhuman from scratch.

Twenty-year-old Annie Chang is one of many who can contain energy inside her body, even replenish it biologically. They plan to attempt to take her, and other "batteries" and increase this natural charge, hoping it'll allow them to power superhuman mechanical suits.