“We had a fake knife and a real knife,” Bender told the outlet over a decade after the series finale aired. “The real knife, like whenever you’re doing a movie, is dulled down. But it is a real blade so it won’t wobble, because all rubber blades do that a little bit.” The director helmed 43 episodes from the show’s first season to its last and also executive produced, so he no doubt had plenty of experience with how prop weapons were managed on set, as would O’Quinn at that time. Bender noted that “Terry was working with a real knife and the fake knife,” using both to make the fight sequence look as real as possible.

From the sounds of it, the real knife was likely used for shots in which it would be more visible, while the rubber prop should’ve been used for moments of actual impact between the actors. “Terry was well-rehearsed in when he would have the real knife in his hand, even though it was dull, and when he would drop it and right next to him, an inch away was the fake knife,” Bender explained. Except, that’s not what happened during one nerve-wracking moment late in the shoot, when O’Quinn accidentally grabbed the real knife instead of the prop. The actor recalls getting caught up in the action of the moment, which involved a grappling wrestle and apparently also featured fire hoses on set to simulate a storm.