There's a bomb on a bus. Once the bus goes 50 miles an hour, the bomb is armed. If it drops below 50, it blows up. As movie premises go, this one is absolutely ridiculous, right? You'd have been forgiven for thinking so, at least, as few involved with Jan de Bont's "Speed," which was released by 20th Century Fox on June 10, 1994, could have anticipated its popularity. The film was a runaway hit, winning two Oscars and grossing over $350 million worldwide. Now, 20 years later, it's a celebrated relic of an era before blockbuster filmmaking was so awash in digital wizardry, an era when practical movie magic sold the highest of concepts to the masses.

For actor Keanu Reeves, who starred as the film's hero, LAPD S.W.A.T. officer Jack Traven, it feels like that long ago if only because so much has changed over the last two decades. Though he had already starred in Kathryn Bigelow's "Point Break," it was "Speed" that turned him into an action star Hollywood would test in films like "Johnny Mnemonic," "Chain Reaction" and "The Matrix" throughout the rest of the '90s. He looks back on the film today as a fond memory in the unassuming early years of his career.

"I think there's something that people respond to in the film in the sense that it feels so accessible and human, in a way," Reeves says. "There's a vulnerability to it. Having participated in that, and having had a great opportunity, and then to be here 20 years later, it feels like that came from a more innocent time."

It also came from a time when audiences only knew actress Sandra Bullock, if at all, from work in comedies like "Love Potion No. 9" or futuristic actioner "Demolition Man" opposite Sylvester Stallone. It was "Speed" that sent her career soaring, but, of course, she couldn't have possibly seen that coming.

"I don't think anyone had any idea what was going to happen with that film," the Oscar-winning actress says. "If someone says they did, they're lying — unless in the editing process they felt something come together. But I certainly didn't feel it. I think we were sort of ridiculed a bit for being the 'low budget bomb-on-the-bus movie.' Not that I cared. I was just so happy to have a job and that I got to work with Keanu. I was grateful no matter what it was."

Indeed, Bullock wasn't at all ideal for Fox at the time. The list of more established actresses who were up for the role is long and considerable, from Meryl Streep to Kim Basinger and all points in between. They all turned it down, unmoved by the outlandish concept. But director Jan de Bont fought for Bullock, who had the girl-next-door look and appeal that he felt the role of bus-riding graphic designer (turned bus-driving heroine) Annie needed.

"Initially every studio wants bigger stars for lead roles, and I understand that," de Bont says. "But I could not see Julia Roberts driving this bus. I could not see several other actresses. I would never believe they would ever even be on a bus. I felt I needed an actress who you could believe would have taken the bus, and Sandra had this kind of every day look – I mean that in a good way — in the way she dresses, the way she behaves, very casual."

The character of Annie was as important as Jack Traven, de Bont says, because "she had to keep this whole team together and keep the tension going. And responses — secondary reactions are really key in movies like this. How real are they? How believable are they? She did a fantastic job on that. She was exactly what I hoped for, and thank God the studio, at the very last moment, let me choose her."

The ever-affable Bullock remains indebted to the director, with whom she worked once more on the film's ill-fated sequel in 1997, for going to the mat for her. "He chose me over so many people that probably would have helped that movie get kicked off in a bigger way," she says. "He gave me the opportunity. So I've got to say, he had some pretty big balls. And I'm grateful for his large balls. And you can quote me on that. And if you can get a visual to go along with that quote, that would be great!"

Filling the bus with reality

De Bont was developing a film about sky-diving at Paramount Pictures when "Speed" first crossed his desk. Even after the studio put it into turnaround, he still maintained an interest in making it his directorial debut because he had a wealth of ideas for how to ground the seemingly fantastical story.

For instance, his desire for a sort of workaday realism didn't stop with Bullock; it also extended to the characters on bus number 2525. It was important to him that the passengers reflect the multicultural world you encounter on the streets of Los Angeles every day. The studio pushed back, but de Bont was adamant that he have a large number of character actors along for the ride. He was interested not only in realism in his choices, but also the sort of intangible quality that comes with casting less-established actors and the honest reactions they can supply in the heat of an action thriller such as this.

"I really wanted people that happened to connect a little bit," he says. "You cannot 'act' out a lot of those scenes."

The very reason the film worked at all, Bullock says, is "because of every face and actor you saw on that bus. There was not one false casting note. You genuinely felt that these people would find each other on a bus, and their level of acting and showing the horror — I mean, we're driving in circles on a bus pretending. They were the ones that I really feel sold the premise and made the movie so good. It could have been so ridiculous, but instead it felt really real and gritty and fresh."

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Nevertheless, Graham Yost's original screenplay presented more opportunities for a number of those actors, opportunities that they lost as the project was developed further (right up until and during shooting, in fact). Joss Whedon was brought on very late in the game to do a re-write that streamlined the film. In some ways it was by artful necessity; many of the actors will tell you the script needed the tightening. But it was also an economic consideration, as de Bont recalls he wasn't able to give speaking parts to everyone who was expecting them due to the amount of residuals they would be owed in perpetuity.

"But I wanted to make sure there was a complete balance between the people that had some lines and the people that had no lines, because they're all the same characters, they all experience the same thing," de Bont says. "I told them, 'Listen, even if you think you're going to just sit on this bus, believe me, you're not, because I really want you to respond and relate to the events and I'm going to put you right in the middle of it. I'm not just going to try to hide you behind some speaking part. No, you're going to get a lot of close-ups. I need your reactions. I want the audience to get the same experience, that this is real; these people just happened to wait at the bus stop and get on and suddenly their lives are changed.'"

Kristopher Tapley has covered the film awards landscape for over a decade. He founded In Contention in 2005. His work has also appeared in The New York Times, The Times of London and Variety. He begs you not to take any of this too seriously.