Lou is relieved to have the past year behind her. Bradley-known as "Sincerely"-is finally in prison, where he belongs. Now settled into a new home and running a new detective agency, Lou has begun a fresh chapter. Michael has retired from the police force and joined her as a partner.
Dani, a longtime friend of Lou and Marianne from high school, is now an FBI agent. She brings Lou a new case to review. As Lou digs in, she realizes she's tracking a serial predator who targets victims through online dating sites-each victim connected to a different platform. It quickly becomes clear that this case is far more complex, and far more dangerous, than Sincerely ever was.