Mary O'Sullivan would rather throw punches than parties. But though her vigilante-league family can fly and support collapsing bridges on one shoulder, Mary’s stuck with her wits, muscles, and a desperate need to prove herself. When the league uses her celebrity secret identity to infiltrate a gala, she takes the opportunity to flaunt her skills as an operative. Mary's decision to bend protocol results in the loss of a dangerous artifact—one that could grant her the power she lacks. Sidelined by the league for going rogue, she pursues the power-granting stone without backup. But she's not the only one looking for the artifact. If she can't secure it, superpowers will be available to the highest bidder—and the league's anonymity could become a thing of the past.