'Paul': Five Secrets Revealed

Among the little-known details about the sci-fi comedy, director Greg Mottola tells MTV News Steven Spielberg lined up his own cameo.

The origin story of "Paul," Simon Pegg and Nick Frost's new sci-fi comedy about two English guys who encounter a goofy alien in the American Southwest, began on the soggy U.K. set of "Shaun of the Dead" in 2003. The crew had lost so many days because of rain that they started wondering how great it would be to shoot in a location where it never, ever, ever rained.

"We just spit-balled from there," Frost told MTV News recently. "No rain became the desert, the desert became Area 51 and then it was a short step to thinking about these two guys encountering an alien."

It's just that sort of strange-but-true tale that we unlocked during a series of conversations with the minds behind "Paul," which arrived in theaters on Friday (March 18). Before you hit the multiplex this weekend, check out four more secrets behind the movie (Beware of mild spoilers below.)

Steven Spielberg Cast Himself in the Movie

From "E.T." to "Close Encounters of the Third Kind," Steven Spielberg's movies loom large over "Paul," a film that is in many ways an homage to the director's oeuvre. He even pops up, albeit in voice only, for a cameo during a flashback sequence in which the alien Paul (voiced by Seth Rogen) gives advice to Spielberg about "E.T."

"He's the one who suggested he be in the movie at all. Simon described it to him and he said, 'Oh, I should do a vocal cameo,' " director Greg Mottola said. "We had one day when we recorded his voice. It was in a sound studio with Seth in his motion-capture suit and Steven at a podium. I was terrified but he was so cool."

"I had to give Spielberg some notes, and he took them," Mottola added. "He's having the 'eureka' moment that E.T.'s finger should glow when he's healing people and I said, 'Steven, I want to hear more of the director's real excitement in the moment of discovery.' I thought, 'I have directed Steven Spielberg. Now I can die.' "

The Original Script Was 180 Pages

The movie runs about one hour and forty minutes, but if Pegg and Frost, who also penned the script, had moved into production on their first draft, the movie would have turned into "a six-hour epic," as Frost put it.

"We wrote 40 pages and then Simon went off to do stuff and I sat in the office and banged out every idea we had and every joke we talked about," he explained. "When Simon came back, I gave him this childish tome and whittled all the rubbish out."

Subplots were cut, jokes were ditched and derivative scenes were chucked. "There was a massive tornado," Pegg laughed, "but we realized we ripped it off from 'Twister.' "

They Really Didn't Want the CGI to Suck

Rogen's alien is a little grey dude with a big noggin and huge eyes -- a deliberate reference to the clichéd alien likeness on so many kids lunchboxes and doctored alien autopsy videos. Mottola and his team ended up spending a huge portion of their overall budget for the computer-generated alien because, well, for the movie to work, Paul had to look freakishly real rather than laughably corny.

"We had to scale down a bunch of other stuff because we didn't have a giant budget. To do the CGI of Paul was one-third of our budget," the director said. "The actual production budget was kind of small. We wanted Paul to look really good and be good CGI and not bad CGI, so we gave up 10 days of shooting and a second unit for the action scenes, just to pour more money into getting Paul right."

They Lucked Out With their House Band

"Paul" doesn't only contain nods to Spielberg flicks but to a wide range of other classic genre movies, from "Star Trek" to "Back to the Future." Proud sci-fi nerds that the entire creative team was, everyone threw in suggestions for cinematic references. For one scene, Mottola proposed having a band in a roadhouse bar play the cantina theme from "Star Wars." He just didn't know if the band he'd hired actually knew the tune.

"They were a local New Mexico band -- and I asked if they could learn the song and they said, 'Oh, we played a wedding for a 'Star Wars' freak. The cantina theme was the first dance,' " Mottola said.

Though the film overflows with sci-fi geekery, Frost and Pegg emphasized that viewers need not be conversant in Klingon to enjoy it. "If this is the first science fiction film you've ever seen, then every science fiction film you see afterwards will be a reference to 'Paul'!" Pegg said.

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

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