The planned release of the $44 million film triggered a virtual ping pong-reaction over the past week. The Sony unit originally canceled the release after it became the target last month of the most destructive cyberattack ever on a U.S. company.
The United States blamed the attacks on North Korea.
The movie, which is playing in theaters in major metropolitan areas as well as in smaller cities ranging from Bangor, Maine, to Jasper, Indiana, features Rogen and Franco as journalists who get recruited by the CIA to assassinate the North Korean leader.
Major movie chains had refused to release the film after threats of attacks on theaters and audiences by hackers. The scheduled screenings in U.S. cinemas do not include major chains.
The entertainment giant backtracked after President Barack Obama, as well as such Hollywood luminaries as George Clooney and Republicans and Democrats in Washington, raised concerns that Hollywood was setting a precedent of self-censorship.
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The film was due to open in some 320 small, independent movie theaters across the United States on Thursday, with many of the screenings having sold out the day before as the controversy over the film made it front-page news around the world.
"You know, this is a film I probably would not have come to see but because of the controversy I thought I would come out tonight to stand up for freedom of speech," said Tamsin Hollow, who showed up for the Los Angeles screening.
Movie fans happy
After watching the film, fans called "The Interview" a great, funny movie.
"It's a farce of the highest level," said Matt Orstein as he left the movie theater. "I would equate it to something like 'Airplane!' or 'Hot Shots!' you know. I mean it's funny but it's definitely nothing that could topple a monarchy."
Fans hailed the appearance by Rogen and Goldberg at the theater.
"It was a great movie, it was really funny, they did a fantastic job. It was really great that Seth came out, Seth Rogen himself came out and greeted everybody. Hey, go America," said Tom Sopit.
The film is also available online in the United States on Google's Google Play and YouTube Movie and to customers of Microsoft's Xbox Video, as well as on Sony's own website for the film.
Multiple commenters on Googleblog said they believed the controversy over the film would drive much bigger audiences than it otherwise would have drawn.
"Thanks N.Korea so many more people will now see it because of what you did!" Gian Carlo Barretto, an IT professional at a Manhattan law firm, said in a posting on the blog.
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Some movie theaters showing the film were taking security measures to protect against any possible attacks.
"We've been working really closely with local law enforcement officials, as have all of the other theaters in the Art House Convergence, a network of independent art house theaters," said Christian Parkes, chief branding officer for Alamo Drafthouse Cinema in Ashburn, Virginia.
Parkes said based on their feedback, he was confident all would be fine for the film opening on Christmas Day.