By 1964, it was possible for a major studio to make a film touching upon the Spanish Civil War without having to answer to some senate investigating committee or other. Based on Emeric Pressburger's novel A Mouse on Sunday, Behold a Pale Horse stars Gregory Peck as a Republican war veteran Manuel Artiguez who continues waging a one-man offensive 20 years after hostilities have officially ceased. Pressburger's novel was loosely based on the last raid of real-life anarchist guerrilla Antonio Sabate who was killed in an ambush in 1959.When the young son of an old comrade in arms comes to the French border village where Artiguez is exiled, he asks the old warrior to avenge the death of his father at the hands of vengeful Nationalist police captain Vinolas played by Anthony Quinn. At first Manuel refuses, but when Manuel learns that his aged mother Pilar (Mildred Dunnock) is dying he's determined to return to Spain to bid farewell to her. Pilar dies before Manuel can embark on his journey, but with the aid of traitorous smuggler Carlos (Raymond Pelligrin) Captain Vinolas keeps up the pretence that she still lives so that he can lure Manuel back to Spain and ambush him. Although a sympathetic priest (Omar Sharif) advises Manuel that he's being tricked, Manuel determines to return at all costs. Aware of the trap that's been set for him, Manuel engages the police in a fire fight, wounding Vinolas, killing Carlos and dying himself in the process.In 1966, Behold a Pale Horse was scheduled to be telecast on a major American network, but was cancelled at the last minute, reportedly at the behest of the Spanish government.