re: Unscripted film shots or accidents that were kept in the final film (other than improv)

“But why male models?”

Everyone on set is stunned as Ben Stiller repeated the same line on accident, having lost his train of thought during the scene.

David Duchovny and Stiller’s wife looked at him in disbelief. Duchovny responded “seriously?? I just told you that”. The mistaken exchange was so authentic and in Zoolander’s character they kept it in the film.