Young Viewers Find ’12 Monkeys’ to Be an Endless Enigma : In “12 Monkeys,” a time traveler (Bruce Willis) who returns to 1996 to head off a viral plague that killed 5 billion people convinces a lovely psychiatrist (Madeleine Stowe) that he’s for real but starts to doubt it himself. (Rated R)

When an intriguing movie preview is perilously confusing, hope springs eternal that it will all become clear in the full-length version. Especially when the star of the preview seems to be Brad Pitt.

But for most kids, it just didn’t happen in director Terry Gilliam’s “12 Monkeys.” First, the story switches back and forth between 1996 and 20 or 30 years hence, when survivors of the disaster have been forced to live underground. Loose ends dangle throughout: Who are the bad guys? What is reality, the future or the past? When are we going to see Brad Pitt again?

Most of all, kids said they were not that interested in piecing together the jigsaw puzzle pieces of the story, told in the signature Gilliam fashion that features a beginning, a middle and an end, but not necessarily in that order.

“Hard to understand,” “Hard to follow,” and “Really confusing” were the conclusions of a group of 12- to 14-year-olds. When did they get confused? “In the beginning,” “And at the end,” “Like, the whole movie,” they said.

Explained Robert Pino, 12, of Laguna Niguel: “They showed the end at the beginning, and the beginning in the middle and the middle at the end.”

Added Mike von Sothen, 13, of Laguna Niguel: “It goes off the subject and then goes to another subject and goes right back, so it’s hard to watch. And it got more hard to understand.”

Jordan Gilbert, 13, of Irvine, was blunt about the denouement. “The ending stunk,” he said. “They didn’t show what happened. I was mad about the ending. I was just mad.”

None of this is to say that Jordan or the others didn’t find other things to like in the movie, or that other kids aren’t comfortable with nonlinear storytelling also featured in Quentin Tarantino’s “Pulp Fiction” and Oliver Stone’s “Natural Born Killers.”

“I liked it a lot,” said Matt del Rio, 14, of Laguna Niguel, who said he liked the editing in “Natural Born Killers.” His friend Eric Harper, 13, of Laguna Niguel, said “splitting the story into parts” reminded him of “Pulp Fiction,” which he also liked.

Brad Pitt, as the deranged son of a prominent virologist, didn’t appear as often as the previews had led them to believe. But they said he was funny as a lunatic who lavishes sarcasm on a modern world that worships commercialism and that allows the torture of animals in laboratory experiments.

Rachel Mashburn, 14, of Coto de Caza, said she was surprised to see Bruce Willis without his trademark smirk and outside his usual action-hero role. As James Cole, a prisoner sent to scope out the origins of the plague that destroyed 99% of the planet’s population, Willis cries nostalgically over “music of the 20th century” but can still administer a fatal beating when needed.

Despite that attack, sporadic graphic language and rear-view male nudity, older kids are unlikely to pick up any bad habits from this film. In the bloodiest scene, Willis, fearing his underground keepers have implanted microchips in his teeth, cuts them out. Said Robert, “I don’t think any kids would just cut their teeth out.”

In fact, Rachel said she was hoping for an action-packed scary movie. In the end, she said, “it wasn’t that scary.”