In 1957 the world is tender and fearful of nuclear weapons post World War II. In an effort to understand and facilitate a neutral global discussion and find some peace, leading scientists and academics-world-renowned "Thinkers"-are invited to a conference in the small town of Pugwash, Nova Scotia, by philanthropist Cyrus Eaton.

Curious about the exciting events when their town is often only ravaged by fires, two local children, Conni and Jamie, take interest in hosting some of the Thinkers-particularly Alex from Russia and Ogawa from Japan. The Thinkers are humbled by the innocent welcome, despite being suspicious of each other, and embrace the children's wonder by opening up about past traumas. But a spy disguised as a reporter has conned Jamie for information to use against Russia, putting the entire conference-and the town of Pugwash-at risk.