The 32-year-old emerging indie film actor was waiting in between takes on the set of the recently released film "Bottle Shock," a story about the early days of California winemaking. And it occurred to him that hanging out is part of his job description.
"You spend most of your time sitting around waiting," he said of being an actor. "Sometimes it's just sitting on a hill. Or talking to (actor) Bill Pullman about robots."
Klein, a self-proclaimed San Ramon Valley High School "drama geek," just rubbed elbows with some of the country's most brilliant independent film directors, actors, cinematographers and screen writers at Sundance Film Festival, where the film was screened in late January.
"Bottle Shock" focuses on a traveling British vintner and a struggling California winemaker during the infamous 1976 blind Paris tasting. The film is based on a true story and simultaneously embraces and pokes fun at wine snobs.
"It's a love letter to the wine industry, to wine and the culture around it," Klein explained.
The movie received mixed reviews at Sundance, but has been praised for its breathtaking cinematography and smart humor. Variety magazine even called it "a peppy and quite deliberate crowd-pleaser."
In the movie Klein plays what he calls a "cellar rat." His character hangs around the vineyard owner's son Bo and is more into partying than tasting tannins.
"He's a bad influence ... He's sort of like the bad devil on his shoulder," Klein said.
He's been cast in the role of several similar "off-center" characters, including many in the realm of the "the quirky best friend."
The film stars actors Bill Pullman and Alan Rickman and is written and directed by Randall Miller, whose most recent films include "Nobel Son" and "Marilyn Hotchkiss Ballroom Dancing & Charm School" with Danny DeVito and Marissa Tomei and featuring Klein in a smaller role.
"He's a real actor's writer," Klein said of the director, who began as an actor. "He's able to speak to actors in a way that relates to them."
When Klein was 14, his family moved from the East Coast to Danville because "Dad was a tech guy" and wanted to be near the Silicon Valley. At first, things were a little awkward, he said.
"I was the really strange new kid from New York," he remembered.
He didn't have any friends going into high school. He talked and acted differently.
"(Kids) would be like, 'Dude, say 'coffee,'" excited to hear his accent.
So he'd say the word with his New York dialect - "kwafee" - and the other 14-year-olds would get a kick out of it.
Eventually he got into theater at the high school and found his niche.
"Doing drama at San Ramon - that's why I'm here now," he said.
From there, he studied theater arts at UC San Diego and was accepted for a summer intensive program at the American Conservatory Theater in San Francisco, which he began the day after college graduation.
Afterward, he moved to New York where he worked in regional and children's theater and a handful of off-Broadway productions. Then he was on to the prestigious London Academy of Music and Arts in 2001.
But soon he realized that film work kept taking him to Los Angeles. So he took some training to convert his theater method of acting (which needs to reach even the couple in the back row) to the more subtle film approach.
"It's a totally different medium. You're not performing, you're talking to the person next to you," he said.
Moving to L.A. was much more pleasant than Klein expected. Coming from Northern California, he'd heard all of the nasty stereotypes about the city.
"In general, we have a stereotype that it's all snobs and plastic faces and whatnot," he said. "It's the tourist misconception."
To avoid people who do fit into that category, it helps to find a group of true friends and stick with them, he said.
He now lives with his Italian greyhound Lucy and is working on a cooking show called "This Man's Kitchen," which has not yet aired. A new flick he acted in called "Killer Movie," about a reality television show that goes awry, is also in production.
On the set of "Bottle Shock," back in northern California, 12-14 hour days were standard. Much of the filming was done outside during sunrise and sunset hours, when cinematographers could catch some of the golden light that makes landscape scenes crisp.
For indie actors like Klein, those hours spent waiting around in between shooting are nothing like the Hollywood "glitz and glamour" he'd heard about while living in Danville. But that was fine by him.
Hanging on a hillside up north, Klein said, is just as good.