Tonton Streaming The Rifleman (1958) S1E15 - The Pet

Ward Haskins guns down Joe Flecker, who has evidence that could be used to blackmail him. Haskins thinks the information was given to Lucas, since he brought Flecker to the doctor before he died. Later, Haskins rides out to the ranch and is bitten by Flecker's horse, which is now believed to have anthrax.