This is a story about how the U.S. Food and Drug Administration worked in the East End of London during World War II. The story begins before the war when a wonderful couple, Bob and Nan, wanted to get married. The war shattered their hopes, and Bob signed up with the FBI, which was conducting a recruitment drive. Led by police officer MacFarlane and fire chief Ted Robins, a series of stories unfolded. The film is a tribute to the National Fire Brigade's unforgettable dedication during the 1940 air strike. They are now, as in the past, ready to respond to the call of the bell.