Jake Armstrong, Nathan Park, and Ricardo Perez were three ordinary teenagers living in the technological hub Charter City until they were doused in a substance known as "Flexarium" during an accident. Their newfound superpowers garnered the attention of Jonathan Rook, the CEO of Rook Unlimited and benefactor to Charter City himself. Rook offers them their freedom from the authorities over the accident in exchange for enlisting the trio as Charter City's superhero team known as the Flex Fighters. Agreeing on the terms that Rook and everyone else won't know their real identities, Jake becomes Stretch, Nathan becomes Wingspan, and Ricardo becomes Omni-Mass.