"Machete" was originally conceived as a fake trailer in "Grindhouse," but fan demand convinced director Robert Rodriguez to make the story into a full-length feature, which opens Friday. The film, which revolves around the titular character and his attempt to clear his sullied name, is full of blood, action, crazy weaponry and beautiful naked and half-naked women.

When we caught up with the "Sin City" and "Spy Kids" filmmaker recently, we asked how he decides when to play the naked card and when to avoid it.

"Ask my sister. She tells me, 'You need to have more hot chicks in this movie!' " Rodriguez said, playfully deferring to his co-editor and co-writer, Alvaro Rodriguez.

"I have a trick," he admitted. "I did this in 'Sin City' too. People say, 'There's so much nudity in "Sin City." ' I say, 'No, if you look close, there's only [some] at the very beginning.' "

Rodriguez said showing a lot of skin from the get-go makes people think they're seeing more than they do. "If you do it at the beginning of the movie, in your mind, everyone is naked the rest of the movie if they're scantily clad -- because that's how the comics are drawn," he said. "['Machete'] was the same way."

Rodriguez cited a particular scene at the beginning of the film, in which Machete tries to save a beautiful (and naked) woman, as his prime example. He said the decision to have the actress appear sans clothing throughout the entire scene helps enable extra tricks in the plot that wouldn't work otherwise.

"That was the first scene I wrote. There's got to be a girl that he goes to save and she's naked and he's having to run out with this naked girl over his shoulder, but then you put a twist on it," Rodriguez explained, continuing with a pseudo-spoiler. "She ends up working for the other side and tricking him by being nude. That way he doesn't see it coming. Everything else, he'd be able to see a trick coming," he said, adding that there isn't much more skin in the rest of the film (save for a topless scene in a pool). "It's really just that trick."

"Machete," starring Danny Trejo, Jessica Alba, Michelle Rodriguez, Robert De Niro and Don Johnson, opens Friday.

What do you think of Rodriguez's trick? Will it affect how you watch the film now? Let us know in the comments!

Check out everything we've got on "Machete."

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