Wanna-be journalist Gunner A. Bush somehow lands his dream job at Rolling Stone magazine. Gunner leaves his hometown of Louisville, Kentucky, to follow in the footsteps of his hero and another Louisvillian, Hunter S. Thompson. Gunner moves to Washington D.C. and hits the campaign trail working for the magazine in the summer of 2016 following both political camps around the country.
As October rolls around, Gunner is yet to be published in the magazine, but he has made deep connections in both political camps. These connections lead him to a rendezvous for an October Surprise. The high-level leak that Gunner lands is the Hollywood Access tape that would make half the world. Gunner is on his way to being published and paid immensely.
Back on the road in St. Louis, covering the Presidential debate in St. Louis, Gunner links up with his best friend from high school, Sawyer Barnes. They party like rockstars, before, during, and after the debates.
Sawyer is going through a divorce and appears to be brainwashed by certain media and planning a mass shooting at his wife's work Halloween party. The details are laid out in his notebook as letters to Kurt Cobain that Gunner accidentally finds and reads.
So Gunner does the only thing he can; he takes Sawyer on the road with him. He wants to keep an eye on him and prevent this from happening. As they drive to Cleveland, Gunner finally realizes his oldest friend isn't the same innocent person he was back in high school. He has become radicalized, and he is adamant that he gets off the road and back to St. Louis before Halloween.
It's a race against time as Gunner tries to figure out how to save his friend from committing an atrocity. Stopping his best friend from committing a mass shooting and suicide isn't his only problem, though, and as the duo returns to Washington D.C, they find the house Gunner has been staying in has been ransacked, fires have been set, and someone left in a hurry. And Gunner's editor at Rolling Stone is dead or missing or worse.