Ultra Ego

["American Ultra" fanfic] Cassie is an underachiever. She's slowly come to terms with being an unimportant nobody that's never going anywhere. But when she gets mugged in an alley she starts developing some serious skills. Turns out she was trained by the CIA to be a lethal killing machine. When the agency learns she's been activated they decide to clean up their mess by terminating all assets and first on their list is Cassie.