JACKSONVILLE, Fla. -- The parents of Sept. 11, 2001, hero Todd Beamer, gave "United 93," the controversial movie about the doomed flight their blessing.

Beamer's parents recently returned home to Jacksonville after watching a special screening of the movie.

David Beamer, Todd Beamer's father, lives in Jacksonville. Todd Beamer was the passenger who yelled, "let's roll" as he and other passengers tried to take down the hijackers on United Flight 93.

Some theaters around the country have refused to show the trailer for the film, saying it's just too soon, and too painful to watch.

However, Beamer's father and other survivors' families have given the movie their blessing.

David Beamer said the film was difficult to watch, but that it's a film everyone needs to see.

"United 93" is a movie about the doomed flight on Sept. 11, 2001, that was intended for Washington D.C, but instead crashed into a field in Shanksville, Pa.

"It's a story that needs to be told. It's realistic. It's violent," David Beamer said. "It's my opinion that every American adult should see it."

David Beamer said he was nervous to see the movie.

"I would say the concern one would have would be how they would tell the story. Would they really tell it right?" Beamer said. "And they did. The courage, the victory in that first battle was all there."

While the public has only seen the trailer, David Beamer has seen the film in its entirety. He said it was difficult to watch, but that it's supposed to be difficult to watch.

Beamer said there's not a day that goes by where he doesn't think of his son. He said a film like "United 93" is not just to remember the victims, but also to remember what they died fighting for.

"It's a great example of Americans doing the right thing at the right time … Answering a call to duty that they never understood was going to be theirs that day," Beamer said.

The film is scheduled to open April 28. Universal said they would donate 10 percent of all proceeds from the film's opening weekend to the Flight 93 Memorial project, a project to have a permanent memorial in the field where the plane went down.