In *Zoolander* (2001), while there was a script, the film is famous for several iconic moments that were either completely accidental or heavily improvised by the cast.
### 1. The "But Why Male Models?" Scene
This is the most famous improvised moment in the film and occurred entirely by accident. During the scene where the hand model **J.P. Prewett** (David Duchovny) explains the elaborate conspiracy to use male models as assassins, he finishes a lengthy, detailed monologue.
* **The Improvisation:** Ben Stiller was supposed to say a different line to continue the scene, but he genuinely forgot what he was supposed to say. To stay in character and keep the cameras rolling, he simply repeated his previous question: **"But why male models?"**
* **The Reaction:** David Duchovny’s bewildered response—**"Are you serious? I just... I just told you that a moment ago"**—was a genuine, ad-libbed reaction to Stiller's "mistake." Both actors stayed in character, and the moment was so perfect for Derek's dim-witted personality that director Ben Stiller kept it in the final cut.
### 2. Billy Zane and the Walk-Off Banter
The interaction between Derek and **Billy Zane** right before the "walk-off" against Hansel was largely unscripted.
* **The Detail:** Billy Zane has stated in interviews that he and Ben Stiller improvised most of their pre-walk-off banter. This includes the famous lines: **"Listen to your friend Billy Zane, he's a cool dude"** and Derek’s high-pitched retort, **"Put a cork in it, Zane!"**
### 3. Will Ferrell (Mugatu) and "Crazy Pills"
Will Ferrell is known for "staged improvisation," where he performs a scene multiple times using different variations of a joke.
* **The Detail:** Ben Stiller confirmed that Ferrell’s iconic explosion of anger—**"I feel like I'm taking crazy pills! Doesn't anyone notice this? I feel like I'm taking crazy pills!"**—was an improvisation in the moment.
* **Alternate Takes:** For the line **"That Hansel's so hot right now,"** Ferrell filmed a "veritable buffet" of alternate takes to see what would stick. Some of the unused improvisations included, "Serve me up an order of hot piping Hansel," and "That Hansel is so hot right now, it'd burn my finger if I touched him."
### 4. Hansel’s Introduction (Owen Wilson)
Owen Wilson’s relaxed, "spaced-out" persona for Hansel allowed for significant riffing.
* **The Detail:** When Hansel is first introduced, he mocks the "himbo" persona of Matthew McConaughey by repeating **"Alright, alright, alright,"** which was an ad-libbed nod to McConaughey's character in *Dazed and Confused*.
* **Philosophical Rants:** Many of Hansel’s nonsensical philosophical musings (like his respect for the music Sting makes even though he doesn't listen to it) were developed through Owen Wilson’s improvisational "play and stray" approach on set.
### 5. The "Walk-Off" Movements
While the framework of the walk-off was scripted, the specific "modeling" moves performed by Stiller and Wilson were largely spontaneous.
* **The Detail:** The actors were given a loose structure to follow, but the actual choreography of their "elaborations" and the breakdance-style posing was improvised based on the music and the energy of the crowd. **David Bowie**, who judged the scene, also played with his lines, reportedly having a "hoot" with the script's absurdity and adding his own flair to the "old school rules" introduction.