The book ‘Challenge Protocol’ is written by Dawn Ryder. ‘Challenge Protocol’ is the 2nd book in the Protocol series. In the story, the character, Cambria, likes her relationships to be simple — hot, satisfying, and under her control. When Dack and Logan enter her life, nothing comes easy for her. The book analyzes Cambria’s journey as she loses control and navigates her feelings for two men who live together, work together, and love together.