The first of the five films where Bill Elliott played a detective lieutenant in the L.A Sheriff's department, Dial Red "O" (the correct title with the number 0 (zero), as on a telephone dial, shown in ") opens with war-torn veteran Ralph Wyatt getting word that his wife is divorcing him, and he flees the psychiatric ward of the veteran's hospital, wanting to talk to her. His escape touches off an all-out manhunt, led by Lieutenant Andy Flynn of the sheriff's department.

Thornton Sayre, a respected college professor - secretly formerly a silent films romantic action hero - is disturbed, feeling his privacy has been violated, and his professional credibility as a scholar jeopardized, when he learns his old movies have been resurrected and are being aired on TV. He sets out to demand this cease. However, his former co-star is the hostess of the TV show playing the films, and she has other plans.

During the Cold War, diplomatic courier Mike Kells must retrieve a dispatch containing top-secret intelligence. But when he arrives at the meeting point, a train station in Salzburg, his contact turns up dead, and the message is nowhere to be found. With no clear suspect in sight, Kells must sort through his uncertain relationships with two women, while sidestepping the pitfalls of subterfuge, sabotage and spies in his search for the documents.