ON THE LINE. It’s 1964 and 24-year-old switchboard operator Agnes (Victoria Lucie– The Devil’s Machine) passes time listening to phone conversations as she connects peoples’ calls in the Channel Islands. However, things take an unexpected turn when she receives a panicked call from Shirley (Harriet Walter), an old woman suffering from dementia who suggests that she’s been kidnapped.
Alerting the police and collecting information from various callers, it doesn’t take Agnes long to deduce who the kidnapper is. As she assists the police in tracking him, things become more and more complex and begin to spiral out of control. Can Agnes save Shirley before it’s too late?