Plot

A group of teenage boys compete in an annual contest known as "The Long Walk," where they must maintain a certain walking speed or get shot.

From Stephen Kings official site: In the near future, where America has become a police state, one hundred boys are selected to enter an annual contest where the winner will be awarded whatever he wants for the rest of his life. The game is simple - maintain a steady walking pace of four miles per hour without stopping. Three warnings, and you're out - permanently.—marcusoft-net

Based on the 1979 novel "The Long Walk" by Stephen King, published under his pseudonym Richard Bachman. In the novel, The Long Walk is a competition in a near-future dystopian society where contestants must maintain a walking speed of at least 4 miles per hour or they're shot dead until only one remains.—moviefansme

In a dystopian future America is under military dictatorship. For entertainment the youth of America enter a lottery with 100 winners. These young conscripts are then the "lucky" entrants in a national phenomenon; a walking race in which the athletes must maintain a pace above 4 miles an hour, with no rests. Escorted by soldiers and live tv cameras the entrants have 3 warnings before a mobile firing squad removes them from the competition. The race winner is the last man walking. His prize is his heart's desire. The boys characters, friendships, hopes and terror are explored as one by one the field narrows. A forerunner of the hunger games, squid game and black mirror, this harrowing Stephen King vision was penned, alongside the Running Man as one of his 4 novellas in the collection of Richard "Bachman Books".