The South African extras on the set of 24 - when the TV drama relocated to Cape Town - were so convincing in violent scenes, filming had to be halted to check they were okay.
24 star Kiefer Sutherland admits intense shooting scenes in South Africa were given an extra edge from locals who had experienced real violence at first hand.
The actor explains, "The people were great. To have the tone and the voice and their perspective - we just had everything from the extras to all the African talent. They were amazing.
"We had extras on a street shoot-out scene and they literally hit the pavement during the shoot-out. We had to stop because we thought people got hurt.
"These people were willing to do this eight hours a day, and they were glad to do it. Extras were coming up with ideas. Finally we just said, 'All of you, just do what you want.'"