The Life of an Assassin/Motif

This novel revolves around Billie, Helen, Mary Alice, and Natalie. The four women are trained assassins whose lives are defined by that fact. Working as Project Sphinx, they have specific habits and skills.

When Billie, Helen, Mary Alice, and Natalie get together for a cruise to celebrate their retirement, the conversation naturally turns to what they will do once they are no longer expected to kill. Only Mary Alice seems excited about this change. Billie is secretly worried that the job has come to define her, and she has no idea what she will do once that is not a part of her life. Right after this conversation, Billie sees a man named Brad who works for the same organization. Billie's first instinct is to greet him, but she quickly realizes that he may have a nefarious reason for being here...