Lady on a train: A young woman on a New York-bound train is witness to a murder outside her compartment window. With a penchant for reading mystery novels and the help of a mystery writer, she sets out to solve the case after police refuse to believe her story. Tangier: The beautiful Maria Montez is determined to bring a Nazi collaborator to justice in this exotic, suspense-filled noir. Take one false step: Follow the trail to the crime-ridden streets...

A three-part British police drama tells the true story of scientist Alec Jeffrey's discovery of DNA fingerprinting in the 1980s and its introductory use by Detective Chief Superintendent David Baker in catching a double murderer.