Tony Lip, a bouncer in 1962, is hired to drive pianist Don Shirley on a tour through the Deep South in the days when African Americans, forced to find alternate accommodations and services due to segregation laws below the Mason-Dixon Line, relied on a guide called The Negro Motorist Green Book.

John Peterson lives with his partner Eric and their adopted daughter in Southern California. When he is visited by his aging father Willis from Los Angeles who is searching for a place to retire, their two very different worlds collide.

A father and his son walk alone through burned America. Nothing moves in the ravaged landscape save the ash on the wind and water. It is cold enough to crack stones, and, when the snow falls it is gray. The sky is dark. Their destination is the warmer south, although they don't know what, if anything, awaits them there.