In the gritty streets of Gotham, 16-year-old Yumi Reyes loses everything when her younger brother, Diego, is brutally attacked by a gang, leaving him in a coma. Fueled by grief and anger, Yumi embarks on a relentless quest for revenge, taking down the gang members one by one. But as she nears the end of her bloody path, she finds herself under the watchful eye of Red Hood, the only member of the Bat Family willing to let her seek justice in her own way. Her vengeance comes at a cost. In a final confrontation, Yumi is fatally wounded, but before she succumbs to her injuries, she is visited by the God of Vengeance. The deity offers her a second chance at life in a new world, where evil is even more pervasive than in Gotham. Granted three wishes, Yumi ensures her brother's recovery, gains a unique system for training and storage, and enhances her ability to withstand cybernetic enhancements far beyond any normal human limits.