"It was taking some chances and it wasn't worrying about being politically correct, but it also had a relatable story and the character," he said. "I think that was the first time you were seeing that, at least with that tone of humor, you know, going that far."
Like "There's Something About Mary," "Tropic Thunder" includes some blisteringly profane language and R-rated gags, which Stiller said is just part of the genre.
"There's a freedom saying, 'hey, it should just be what it is.' I mean, I don't know. I feel like people know what they are getting into if they come into an R-rated movie," he said.
One of the people dropping swear words is Tom Cruise. Years earlier, Stiller had cut short his honeymoon to do a short film in which he played Cruise's "Mission: Impossible" stunt double.
"We both had a good time doing that," Stiller said. "I think, after that, we kind of stayed in touch."
Stiller said it will be fun for audiences to watch Cruise in this movie "because he really takes some chances."
So, has Stiller become one of those Hollywood types his movie mocks?
"Well, I think that's why I made this movie," he said. "All of a sudden it's just sort of you can have this, and you can have this, and you have to be careful about that."
"You know, my wife will call me on it," he said. "I just also think it's the nature of the stressful nature of making movies, where there is, like, where you are in a situation where you are called on to do a scene and be funny, and do this, and 'people, can you now go a little cuckoo?'"