The Virginian (1962)

S4E28 No Drums, No Trumpets

Starr, accompanied by Trampas, decides to travel to Mexico to assess the safety of a town where a U.S. Senator and a Mexican Governor are set to finalize a treaty. Initially, everything seems fine, prompting Trampas to depart. However, Starr quickly discovers he has become entangled in a conspiracy to carry out an assassination.