Barry Cohen, who attended the 1:30 p.m. screening with his wife and grown son, said they "had no idea" what was going on.
"When it lasted more than five seconds, we though that maybe it was part of the movie and then we realized that it wasn't," Cohen told ABC News.
Even though a power outage would have caused confusion in any circumstance, the threat issued by a hacking group that it would attack theaters screening "The Interview" led to understandably hyped tensions, moviegoers said.
"Some people ran out of the theater," Cohen said. "There was another couple near us, the woman turned to her husband and said, 'Let's get out of here!' She didn't even wait for a refund or anything."
Allwood Cinemas did not immediately respond today to a request by ABC News for comment, but a spokesperson for the power company, Public Service Electric and Gas Co., confirmed that there was an outage in Clifton on Thursday afternoon.
"At 4:01 p.m. on Thursday, December 25, a downed wire on Market St. caused approximately 1,300 customers to lose power in Clifton. PSE&G crews arrived on the scene and restored power to all customers at around 4:15 p.m.," PSE&G spokesperson Lindsey Puliti said in a statement.
Cohen said that after realizing that the blackout was not part of the movie, he went out into the lobby -- where the lights were still on -- and asked for a refund once it was clear that the theater was not going to be able to rewind the scene to fill in the gap.
He and his family got refunds, went home, and downloaded the movie on Google Play so that they could see the final 15 minutes, Cohen said.