At the end of the Civil War, Jim Slade, a young confederate soldier and conscientious objector, returns to his ranch to find his parents murdered and the ranch practically destroyed. He finds and kills three of the murderers and learns the name of the fourth, a certain Corbett. Finally he discovers Corbett as the leader of a gang that has plans to rob a local bank and is invited to help defend the town from the bandits. Teaming with a preacher, who has an agenda of his own, the two take a stand against Corbett.
Unfortunately the movie A Gun for One Hundred Graves is not yet available on HBO Max.
| Directing | Umberto Lenzi | Director |
| Directing | Francisco Ariza | First Assistant Director |
| Directing | Roberto Giandalia | Script Supervisor |
| Production | Fernando Rossi | Unit Manager |
| Production | Lamberto Andreani | Production Secretary |
| Production | Ignacio Gutiérrez | Production Secretary |
| Costume & Make-Up | Vicente Vázquez | Makeup Artist |
| Costume & Make-Up | Raul Ranieri | Makeup Artist |
| Costume & Make-Up | Maurizio Trani | Assistant Makeup Artist |
| Costume & Make-Up | Marisa Laganga | Hairstylist |
| Camera | Raúl Pérez Cubero | Camera Operator |
| Camera | Renato Doria | Assistant Camera |
| Camera | Francesco Narducci | Still Photographer |
| Camera | Miguel Guzmán | Still Photographer |
| Sound | Pietro Spadoni | Sound |
| Art | Saverio D'Eugenio | Production Design |
| Art | Jaime Pérez Cubero | Set Decoration |
| Art | José Luis Galicia | Set Decoration |
| Costume & Make-Up | Walter Patriarca | Costume Design |
| Editing | Daniele Alabiso | Editor |
| Sound | Angelo Francesco Lavagnino | Original Music Composer |
| Production | Averoe Stefani | Production Manager |
| Writing | Eduardo Manzanos | Story |
| Writing | Marco Leto | Screenplay |
| Writing | Umberto Lenzi | Screenplay |
| Camera | Alejandro Ulloa | Director of Photography |
| Production | Salvatore Alabiso | Producer |
