Zero Days

Zero Days, the eighth novel by British writer Ruth Ware, is a psychological thriller featuring a resourceful, self-reliant female protagonist, Jack Cross. Jack, who narrates the novel, returns home from a routine corporate security job to find her husband, Gabe, brutally murdered. Jack becomes the prime suspect and goes on the run to find the killer. Jack uncovers the cybersecurity threat her husband was murdered to keep secret, a security flaw that allows criminals to harvest personal information about children. Jack learns appearances can deceive but is helped time and again by strangers. In the end, one final surprise gives her a reason to go on when she thought her life had lost its meaning.

This guide refers to the First Scout Press hardcover edition published in June 2023.

Content Warning: The source material features discussions of abuse and stalking and mentions a possible suicide.

Plot Summary

Jack Cross is breaking into an office building in London. With her husband, Gabe Medway, on Bluetooth, she reaches the computer servers and gains access to company records. As she leaves, she is apprehended by security and taken to a police station. She explains that she is a “pen tester” (penetration tester) hired by companies to find security vulnerabilities.