I saw a man walk into my camera viewfinder from the left. He took a pistol out of his holster and raised it. I had no idea he would shoot. It was common to hold a pistol to the head of prisoners during questioning. So I prepared to make that picture - the threat, the interrogation. But it didn't happen. The man just pulled a pistol out of his holster, raised it to the VC's head and shot him in the temple. I made a picture at the same time. (On his 1968 photograph of the summary street corner execution of prisoner Nguyen Van Lem by South Vietnam's police chief, Lt. Col. Nguyen Ngoc Loan.)