The young woman called Penance possesses the mutant ability to internalize negative energy around her, turning her body into a diamond-hard, razor-sharp weapon. Held prisoner by the energy-stealing mutant Empath for an undetermined number of years, she escaped and was transported to the doorstep of Xavier's School for Gifted Youngsters. Now, Banshee and Emma Frost face the challenge of reading out to help a girl who can slice apart anything she touches.