They looked alike, fought alike…but when it came to spy games, Samantha St. John and Elle Petrenko had different codes.

Upstanding CIA agent Sam played by the rules. Russian spy Elle had more colorful ways of getting the job done. Ways that put her at odds with her newfound sister–and in the path of one dangerous male.

Sam's loyalties lay with her former classmates, the women of Athena Academy who'd asked her to find a link between a blackmailer and her parents' deaths. But Sam needed Elle and her mystery man to succeed.

Could the sisters' newly formed bond survive this personal mission, the heart of which might reveal a devastating truth about their past?