Ewan McGregor got aroused while filming the BBC play Scarlet And Black.
“I had to lie on top of her and they kept on pulling back the sheet," he said. "They wanted to see my naked bum and her naked thigh, so we couldn’t wear any underwear. It was very embarrassing. It was a case of, ‘Cut! We’ll go again.’ I calmed my [erection] down and we just got on with the scene.”