When Steve Jobs was in charge of Apple, the launch of a new electronic gizmo was a major media event, cloaked in secrecy and elaborate stagecraft to maximize anticipation and impact. It’s a technique that the team behind jOBS has taken to heart based on Friday night’s red-carpet movie premiere at the Sundance Film Festival. A grand unveiling — featuring Ashton Kutcher and Josh Gad, who plays Apple co-founder Steve Wozniak — finally put the film’s operating system on display after months of speculation.

There had been one slight hiccup: Yesterday, Open Road had released a 62-second video clip from the movie, providing the first extensive look at the actors resembling Jobs and Wozniak in the 1970s. Which was fine until Wozniak publicly called the scene “totally wrong.” (It’s worth noting that Wozniak is consulting on a rival Jobs biopic with Aaron Sorkin.)

“I was surprised and bummed that he responded to a single clip,” Gad told reporters, “because I think there’s much more to discover in the film’s totality and we really set out to honor his story.”

The movie tracks about 25 years of Jobs’ life, beginning with his days as an uninspired student at Reed College in Oregon and culminating in his return to the top of the innovative computer company he co-founded. Kutcher’s resemblance to the corporate iconoclast, who died of cancer in 2011, is at times eerie, but the actor expressed his terror at tackling the role. “He’s fresh in our mind,” Kutcher said, during the post-screening audience Q&A. “I’ve never seen Lincoln walk into a room, but I’ve seen Steve Jobs walk into a room, so I knew I was throwing myself into massive amounts of criticism.”

Kutcher’s obsession with Jobs — he says he watched 100 hours of footage to capture his walk and talk — pushed him to great lengths to capture the essence of the polarizing CEO. He said that he attempted the famously particular Jobs’ fruitarian diet and quickly found himself in the hospital with a pancreatic ailment two days before filming began.

As anyone who’s read Walter Isaacson’s biography of Jobs knows, Jobs was a complicated man whose intensity and focus could inspire others to great heights even while his churlishness alienated many of those closest to him. Kutcher wasn’t above using that for fuel, either, and if that meant provoking his costars in order to get the right ambivalent reaction when the cameras rolled, well, so be it. “I showed up to work and played Steve Jobs every day, so definitely I probably wasn’t the most pleasant I could have been as a person,” Kutcher admitted. “I think when we were working on the film, I tried to care with the same intensity for the film that he cared about his products, so I’m sure I brought a little bit of a short temper to work.”

Oh, and one more thing: jOBS opens in theaters April 19.

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