WonderCon 2012: 'Battleship' Director Peter Berg on Movie's Aliens, Inspiration From Stephen Hawking

Peter Berg - Head Shot - P - 2011
Chris Haston/NBC
The director also revealed that Kevin Costner shared pitfalls of water filming learned from making the famously expensive flop "Waterworld."

Universal invited fans aboard its Battleship on Saturday at the WonderCon convention in Anaheim, showing plenty of footage, characters and, yes, even revealing the aliens at the center of its big summer movie.

With co-stars Brooklyn Decker and Alexander Skarsgaard sitting next to him, director Peter Berg kicked off the presentation by explaining his decision to include aliens in a movie adaptation of a Hasbro board game that does not feature aliens.

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While he has plenty of respect for Navy history, Berg said he wanted to make a film that felt more fun than a traditional military film. The idea for the aliens, he said, came from watching a documentary in which Stephen Hawking talked about Goldilocks planets, which have been identified as having potential for life. Governments on Earth have sent radio signals to these planets attempting to discover if anyone is out there.

"And he says, 'This is a horribly stupid idea.' If they are out there, we should not be trying (to reach them)," Berg explained.

The production has taken heat from some quarters for casting R&B star Rihanna in the movie (it's her acting debut), but Berg defended singers-turned-thespians. He pointed to Frank Sinatra as one who made a memorable transition and said he "personally had great success in Tim McGraw (who appeared in Berg's Friday Night Lights and The Kingdom). They make great actors."

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Added Berg: "Rihanna asked for no special treatment, she stayed in the same crappy hotels we did, and she said 'Treat me like an actor.'" 

Berg, in a relavatory mood, also said how a month before filming he got a call from Kevin Costner, which elicited laughs from the audience since Costner is responsible for making one the biggest water movie flops of all time, Waterworld.

"'I feel compelled to talk to you about what we did right and wrong,'" Berg
said Costner told him, adding that Costner talked to him and his line producer for about three hours.

It still didn't truly prepare Berg for the hardships of filming on water; on the production's first day, the cinematogprher got sea sick, star Taylor Kitsch was injured, and one crew member quit.

VIDEO: Battleship Trailer 3

The presentation showed two extended scenes, giving the crowd a major sense of the movie, and also premiered the latest trailer, which will be shown in front of Wrath of the Titans.

The presentation was a stark contrast to Fox's Prometheus panel, which while showing a slick trailer, still kept many things close to the vest.