John Garrity, his estranged wife and their young son embark on a perilous journey to find sanctuary as a planet-killing comet hurtles toward Earth. Amid terrifying accounts of cities getting levelled, the Garritys experience the best and worst in humanity. As the countdown to the global apocalypse approaches zero, their incredible trek culminates in a desperate and last-minute flight to a possible safe haven.

Years following the events of "The Shining," a now-adult Dan Torrance must protect a young girl with similar powers from a cult known as The True Knot, who prey on children with powers to remain immortal.