True-crime podcaster Elle Castillo has been obsessed with The Countdown Killer for decades. Twenty years ago, he established a gruesome pattern of taking and murdering three girls over seven days, each a year younger than the last. No one's ever known why he followed this pattern, or why they stopped abruptly after the eleventh victim. Most believe him to be dead. Elle knows he is not and is hellbent on serving historic justice.
When the kidnappings start up once again, Elle must confront her responsibility in forcing the killer out of hiding. She needs to stop the deadly countdown and convince both the authorities and her podcast audience, before the Countdown Killer can claim his next victim.