Johnny Marinville is one of the protagonists in Desperation. He is a best selling author touring the country on his Harley Davidson. Johnny is abducted by Collie Entragian and thrown into the jail with the others. Initially Johnny is skeptical of David Carver and is constantly looking to explain away the situation. After he accepts that Tak is real he refuses to follow through with God's mission, but he eventually changes his mind. He assumes leadership of the survivors and sacrifices himself to close off Tak's access to our world.
In the novel there is an extensive backstory on Marinville. Marinville is divorced, a recovering alcoholic and drug addict. He went to Vietnam as a young writer working for a magazine (possibly based on the real-world author Michael Herr) and that experience has never left him. It is later revealed that Johnny was killed in Vietnam, but returned to the world of the living. Johnny is highly intelligent, egotistical and self-destructive. However he is capable of being surprisingly brave, resourceful and unselfish.