In 1964, Harpoon and King Yeller, two young musicians on the verge of being drafted, head down to Mississippi to visit the fabled Robert Johnson crossroads so Yeller can make a deal with the devil for fame. Yeller pays a blood sacrifice at midnight, but what answers his summons is not the devil; it's a being far more sinister. Under the tutelage of this bizarre stranger, Yeller soon becomes a Delta blues sensation. But with success comes a maddening secret that is eating him away. A secret that will bring blood and insanity if it ever gets out. And Yeller must let it out. Only then can he master the greatest song anybody anywhere's ever heard – The Crawlin' Chaos Blues.