This is a terrifying film is a British animated film written and directed by Peter Foldes and his wife, Joan. It is narrated by James McKechnie. Created after the United States first detonated a hydrogen bomb in 1952, the film depicts the complete annihilation of the Earth and all life on it. The film gained the attention of the mass-media in 1956 after it was aired on The Ed Sullivan Show.
What makes this really terrifying is the thoughts it puts in your head. Sure the Cold War of the 80s is long past, but there are still enough nukes around to make this movie seem like a best case scenario.