Steven Spielberg’s early-career made-for-TV thriller Duel famously never revealed the identity of its villainous truck driver, and the director had a specific motivation for this creative decision. Spielberg’s second feature-length directorial effort after his Name of the Game episode, “L.A. 2017,” Duel stars Dennis Weaver as a commuter on the run from a dangerous trucker. The screenplay by Richard Matheson was adapted from his own short story of the same name, originally published in Playboy magazine. It won the Grand Prize at the 1973 Avoriaz Fantastic Film Festival and an Emmy for sound editing, and is now a beloved cult classic revered as one of the all-time greatest made-for-TV movies.

While driving across the California desert to meet with a client, a business commuter – played by Gunsmoke star Weaver – finds himself tormented by the driver of a semi-trailer truck, who is determined to run him off the road. The everyman protagonist (aptly named Mann) enters into an intense rivalry with the truck driver that leads to deadly consequences. Carey Loftin, a renowned stunt performer who worked on such iconic car movies as Bullitt, Vanishing Point, and The French Connection, was the stuntman who drove the truck. But the truck driver’s identity is never shown on-screen, and that’s an important part of Spielberg’s telling of the story.

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Steven Spielberg Wanted To Add A 'Supernatural' Effect By Not Revealing The Truck Driver

Mann sees the truck in his rearview mirror in Duel

In an interview with fellow filmmaker Edgar Wright for Empire magazine, Spielberg explained that he concealed the truck driver’s identity in Duel to give the film a “supernatural” quality. When Wright suggested Duel has “hints of it being a supernatural horror without it ever being explicitly that,” Spielberg replied, “The supernatural horror really does not take place on the screen. It takes place in the minds of the audience.” According to Spielberg, hiding the truck driver’s face forced the audience to use their own fears and imagination: “By not showing the driver, the audience gets to make any substitution they choose. And that’s where it takes on a supernatural vibe.”

Leaving the truck driver’s identity to the audience’s imagination is fiercely effective, and makes the movie more terrifying. Spielberg went on to utilize a similar technique with his breakout theatrical movie, Jaws. Just as the truck driver remains unseen throughout Duel, the 25-foot great white shark is largely unseen throughout Jaws. Spielberg had learned from Duel that what the audience imagines lurking beneath the surface of the ocean – just like what they imagine sitting in the cab of a semi-trailer truck – is much more horrifying than anything he could show on-screen.

Steven Spielberg Hinted That The Truck Driver Was A Serial Killer

The truck sneaks up on Mann's car in Duel

In “Duel: A Conversation with Director Steven Spielberg” (available on YouTube), the director hinted that the antagonistic truck driver in Duel was a serial killer. Spielberg said, “The intention was that he was basically a marauder in every state,” and pointed to the various license plates on the front of the truck as evidence of his murderous past. In this sense, the truck driver is a classic slasher movie villain. This ominous visual detail hinted that the trucker had been driving across America, targeting unsuspecting commuters like Mann, and these license plates were taken from vehicles he ran off the road in other states

The suggestion of an unseen backstory makes the character feel more real. The threat of this truck driver extends beyond the runtime of Duel. Mann isn’t being targeted at random by a one-time stalker; he’s the latest in a long line of this truck driver’s victims. Since the truck driver has succeeded in killing so many previous motorists, Mann’s chances of survival seem even slimmer. It’s easy to see why Spielberg was given the job of bringing Jaws to the big screen after terrifying TV audiences with his work on Duel.

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