No one knows how the first book-to-film critics panel at BookCon will go, least of all Matt Atchity, the editor-in-chief of the online film review site Rotten Tomatoes, who is going to be moderating. But expecting the unexpected is part of its fun, he insists, and the spirit of the event is right there in its title, “Your Opinion Sucks! Special Edition: Rotten Tomatoes Critics vs. Fans; Best to Worst Book-to-Film Adaptations”; the panel meets today, 12:30–1:30 p.m., in Room 1E16.

“No two panels are ever the same,” says Atchity. He notes that Rotten Tomatoes—which has been part of the film-going world since 1999—has managed a few film critic panels at other conventions, including ComicCon and C2E2 in Chicago. But Atchity expects that the topic of films adapted from books will be especially exciting because people have great attachment to—and expectation of—adaptations of their favorite books.

Drawing from his own experience, Atchity says he rereads Tolkien’s Lord of the Rings books every few years, yet he still thinks Peter Jackson’s films are great. James Ellroy’s L.A. Confidential, he says, might be an even better example of taking a complicated book with a bunch of twists and turns and making it into a great—and not 12 hours long—movie. The adaptation of Mark Helprin’s A Winter’s Tale, he predicted, would not fare as well.

Rotten Tomatoes has lined up freelancer John Anders, Steven Whitty of the Star Ledger, and Joe Neumaier from the Daily News to be on the panel. Atchity says there is no set agenda, and the conversation will reflect the mood of the room.

At ComicCon, Atchity recalls, a “brave” teenage boy got up and declared that he hated Pixar’s award-winning film Wall-e. “People booed” in a good-atured way, says Atchity, “but he also made some good points.”

The only sure thing Atchity will say about the book-to-film panel is that he expects the hour to go by quickly. “Line up early,” he advises those who wish to join the conversation at the microphones that will be set up in the audience.

“It’s a great opportunity for fans to debate the critics all in good fun,” he says.