Vortex : an FBI thriller
(Book)

Series numeration from www.goodreads.com.

Seven years ago Mia Briscoe was at a frat party with her friend Serena when a fire broke out. Serena was never heard from or seen again. Now an investigative journalist, Mia covers the political scene in New York City, but she hasn't given up trying to find out what happened to her friend. When an old photo taken at the frat party gives her clues, Mia enlists Sherlock's help to uncover a sinister string of events going all the way back to that disastrous party. CIA Operative Olivia Hildebrand was nearly killed by a grenade on a mission in Iran to exfiltrate a betrayed undercover operative. Now the team member who saved her has disappeared-- and two men come to her house to kill her. Savich believes the attack was a direct result of the compromised mission in Iran. -- adapted from jacket