Why Paul Rudd Decided to Play 'Ant-Man'

— -- Funnyman Paul Rudd, who is best known for his roles in cult classics like “Clueless” and “Anchorman,” may seem like an unusual choice for the superhero lead in Marvel’s new action adventure, “Ant-Man.”

But Rudd thinks that’s exactly what filmmakers were going for.

“Marvel seems to have this history of casting people and putting people in films that you would not necessarily associate with that kind of thing,” Rudd told “Nightline.” “I think that was part of the appeal for them, that I had never done anything like this. It was certainly part of the draw for me.”

In fact, Rudd helped co-write the script, adding his trademark sense of humor and giving this adventure film a comedic twist.

“I mean, it is funny,” he said, laughing. “Look, I'm riding around on an ant.”

Unlike Marvel’s other larger-than-life action heroes, such as Wolverine or The Incredible Hulk, Rudd’s character, Scott Lang, is a tiny superhero who can shrink down to the size on an ant with superhuman strength and on a mission to save the world.

“Most people aren't familiar with Ant-Man, first of all,” Rudd said. “But then when you tell people, ‘Well, he shrinks to the size of an ant,’ basically that means you're invisible.”

To play Ant-Man, Rudd has to strip down a little in the movie to suit up, which he said was “a great motivator” for getting in shape.

“I certainly exercised and trained. ... Little carbs. No cookies. No alcohol,” he said. ““My suit was real. ... I am a little biased, but I think it's the best-looking suit.”

With a reported $130 million production budget, the film uses special macro photography to capture the action sequences from the point of view from an ant. Rudd is joined by an all-star cast that includes Evangeline Lilly and the legendary Michael Douglas.

Douglas plays Hank Pym, Scott Lang’s mentor and the mastermind behind the Ant-Man suit. It’s his first superhero movie.

“You know, look, couple my best buddies [were in superhero movies] -- Jack Nicholson, Danny DeVito, the Penguin, you know, the Joker," Douglas said. "And so this came along, and I couldn't have been happier.”

“Ant-Man,” which opens in theaters nationwide Friday, is expected to maintain Marvel’s streak of No. 1 opening weekends. And after this, both Douglas and Rudd joked they have a new found appreciation for ants.

“I have a total, total respect for ants,” Rudd said. “I would never flick them. I don't smush them. I don't set ant traps. I let them alone. They're my brothers and sisters.”

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