Jason Clarke (standing), Tom Hardy (left) and Shia LaBeouf are the Bondurant brothers, real-life bootleggers from 1930s Virginia, in the new film “Lawless,” based on the book by Mount Vernon High grad Matt Bondurant. (Richard Foreman, Jr. /SMPSP)

But first: This movie is terrific. It’s based on Matt Bondurant’s second novel, “The Wettest County in the World,” written while he was teaching at George Mason University, and focuses on his family’s exploits in the bootlegging business in southwestern Virginia in the 1930s. It was a violent business, it is a violent book, and this is a violent movie.

Still, Tom Hardy as Forrest Bondurant simply dominates the screen. His mumbled grunts are more expressive than any full sentence. Guy Pearce as the vicious Charlie Rakes is perfect, as always. Jessica Chastain is a vibrant splash of color in an otherwise grime-coated world. And Shia LaBeouf? Not previously one of my favorites. But here, as Jack Bondurant, the protagonist who goes on the classic Hollywood-ized journey from underdog to victor in three acts, he is simply superb. When he finds out his best friend is dead? Well, it got mighty dusty in there.

The audience loved it. They laughed often at the great screenplay by Nick Cave. They gasped at the blood. They applauded at the end. It was totally riveting and went by in a flash. (And thus concludes my obvious attempt to be quoted in a movie ad.) It opens nationwide Aug. 31. The long version of the trailer is below, and highlights from the Q&A are after the jump.

The Q&A was interesting because we not only had the author, but also his father. Jack Bondurant Jr. is the son of Jack Bondurant, the focus of the book and the movie. He grew up in Franklin County, Va., where the story takes place, and he said he was amazed by how well the filmmakers had recreated it, even though it was shot in Georgia.

His father, played by LaBoeuf, has some, er, tough times in the movie. ”After watching it,” Jack Bondurant Jr. said, “I guess I’m glad to be alive.”

He said some of his family was not particularly thrilled with his son’s book, but had mostly come around to the fact that this was part of their history, it’s over now, and they went on to lead lawful lives. The movie has a postscript which makes that clear, and Jack Bondurant was glad for that.

Author Matt Bondurant, a Fairfax County native and Mount Vernon High School graduate. His second novel, “The Wettest County in the World,” has been made into the major motion picture "Lawless." (Tom Jackman/The Washington Post)

Matt Bondurant told the audience what he’d told me in May, that he first saw the film through the prism of the story and character choices made by Cave, who never spoke to him. But he liked it more the second time, and on Monday’s third viewing, he liked it even more.

Matt Bondurant also said he was sorry to see Sherwood Anderson, the American author who was actually in Franklin County reporting on bootlegging at the time, dropped from the film, though he understood the reasons. He said some scenes featuring his uncle Howard, a major character in the book played by Jason Clarke, were filmed but edited out, which he hated to see go. He said Clarke actually spent time with the Bondurant family in Franklin to research the role and remains friends with them

But he said the filmmakers were very gracious with letting him see scripts as well as an early cut of the movie itself, even though they weren’t required to do so. And now, the Mount Vernon High School and James Madison University grad is headed off to a number of other cities for similar screenings, but without his family in tow.