Every week a look at a different item in the Black Museum of Scotland Yard is presented by Orson Wells. Sometimes a typical weapon of murder, and sometimes a mundane household item. Today a regular reciept for the purchace of ten gallons of gas is the key piece of evidence that the justice for a murder hinges upon.
Late in the night, a cop pulls over a car, and is gunned down by the driver. The wires of communication are soon buzzing as the police are especially determined to bring down a cop killer. Clues are gathered, a stolen car is reported, and a dragnet is sent out with police on the alert. No fingerprints, or any traces of the criminal are found in the stolen car, and a profile of likely suspects has to be developed based on the manner of the crime.
Over the span of several days, a crime spree of armed robbery and stolen cars plague Scotland Yard. Will the cops be able to close in, or catch up? Can they anticipate the next moves of their man to set a trap? Tom Green has plenty of alibis, and is ahard nut to crack. Some hard evidence will be needed to blow Tom’s story apart. After an intense police search that gasoline reciept is turned up to bring this to a sudden close.