Screaming Mantis was the leader and psychological warfare specialist of The Beauty and the Beast Unit. She, along with the other members, suffered from Post Traumatic Stress Disorder.
While in the Middle East, Screaming Mantis and the rest of her Beauty and the Beast Unit were spotted by Snake attacking a group of rebel soldiers. Mantis used her ability to control a person's nanomachines, allowing her to lift a rebel soldier completely off of the ground and contort his body into a sick, twisted knot, instantly breaking all of the bones in his body. She also turned the very same soldier on his own comrades, aiming his assault rifle at their backs and killing them before they were able to fire an RPG-7 at Crying Wolf. Then, suddenly, with a wave of her arm, The Beauty and the Beast Unit withdrew, leaving Snake in awe at their power and ferocity.
Much later, during the final assault of Outer Haven, Snake finally came face to face with The Beauty and The Beast's leader. After disposing of a large unit of FROGS inside Outer Haven's command center, Screaming Mantis appeared before Snake, using her Psycho Mantis doll to take control of Meryl and point her Desert Eagle at Snake. Snake was able to quickly subdue Meryl by suppressing her nanomachines, while Mantis took control of the FROGS scattered around the room using her Psycho Mantis and The Sorrow dolls.
Unfortunately for Mantis, though, Snake was able to see through her techniques, and also injected himself with the nanomachine suppressor. After knocking her dolls free of their strings, Snake was able to snatch them up and use them on her. Despite her bond with Psycho Mantis and her strong mental force, she was unable to suppress her nanomachines, and Snake ironically used the Psycho Mantis doll to destroy her.
