Growing up in post-World War II era Arizona, young Sammy Fabelman aspires to become a filmmaker as he reaches adolescence, but soon discovers a shattering family secret and explores how the power of films can help him see the truth.

In the early evening of August 21, 2015, the world watched in stunned silence as the media reported a thwarted terrorist attack on Thalys train #9364 bound for Paris--an attempt prevented by three courageous young Americans traveling through Europe. The film follows the course of the friends' lives, from the struggles of childhood through finding their footing in life, to the series of unlikely events leading up to the attack. Throughout the harrowing ordeal, their friendship never wavers,...