Charles Durning almost drowned while shooting the scene in which his character is thrown into the river. The crew forgot him and left. Gregory Peck jumped into the water and swam to save him.
Many people consider this Gregory Peck's worst film. According to Peck, "What audiences saw was not the picture we set out to do. John Frankenheimer, the director, left immediately after it was finished to do a picture with Omar Sharif in Europe. The studio people eliminated the prologue and epilogue, which gave some sense to the story. They had Johnny Cash write songs, which simply reiterated the action on screen. Everytime I see Frankenheimer he says, 'I owe you one.'"
The scenes in town were filmed in Gainsboro, Tennessee.
John Frankenheimer wanted Gene Hackman for the lead after working with him on Los temerarios del aire (1969), but Columbia insisted on Gregory Peck.
The dam shown is Center Hill Lake on the Caney Fork River, in DeKalb County, Tennessee. Some of the rural scenes were shot on Dry Creek, which is also in DeKalb County.