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The death of actor Paul Walker in an automobile accident Saturday has left fans and the film community reeling — and Hollywood facing a series of tricky business decisions.

As filmmakers and fellow performers remembered Walker as a deeply likable everyman with a taste for adventure, principals on the late actor's signature "Fast & Furious" franchise were left to deal with Walker's tragic passing on the screen.

Walker's death, in a single-car crash in Valencia, came as the Glendale native was preparing to resume production on "Fast & Furious 7," with a return to the Atlanta set scheduled for Monday to shoot more scenes as rogue ex-cop Brian O'Conner.

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Earlier in the fall, Walker had shot an unspecified number of scenes for the car-themed action picture, which this go-round centers on a vengeful rivalry between racing crews.

With Walker's death, director James Wan, lead producer Neal Moritz and executives at Universal Pictures have a decision to make on the film, set for release July 11.

It's believed that there is not nearly enough material in the can to close O'Conner's character arc in the picture, which would mean rewriting the script to allow for a new resolution — a complicated and timely process — or cutting Walker out of the film entirely. Walker's planned scenes this week will almost certainly mean a schedule shuffle and could also lead to a halt in production.

Universal would not comment beyond a brief condolence message sent to reporters by a spokeswoman late Saturday. Moritz did not reply to a request for comment on plans for "Fast 7" in the wake of Walker's death.

While the sudden passing of a director can throw an entire project into jeopardy (Tony Scott's suicide in summer 2012 effectively derailed a planned "Top Gun" reboot) actor deaths have often meant a posthumous release as a tribute of sorts--providing their work has been completed. James Gandolfini, Heath Ledger and James Dean all had well-received films released after their death. Walker's role in "Fast 7," though, is a particular P.R. tightrope walk for Universal, given both the circumstances of his death and the fact that he was not finished shooting the film.

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Walker's passing also raises questions about the long-term viability of the series. "Fast & Furious" movies have grossed $2.3 billion worldwide, with the most recent, 2013's "Fast Six," the highest-grossing ($789 million).

While the series — which already has an eighth film in development — has rotated characters in and out over its 12-year history, the nucleus has been the buddy dynamic of Walker's O'Conner and Vin Diesel's Dom Toretto, who have been in every movie but "The Fast and the Furious: Tokyo Drift," the series' least successful installment. Still, many in Hollywood expect it to continue, with the brand considered a larger draw than any single performer.

Walker, 40, died as a Santa Clarita charity event and car show was winding down, when he and friend Roger Rodas went for a ride in a red Porsche, a witness said.

Jim Torp heard a loud boom and said he knew in his heart that his friends had been in an accident. The smoke from the crash was visible from Always Evolving, the automotive shop where car enthusiasts and supporters were gathered. The event was held in support of Walker's first-aid organization, Reach Out Worldwide, with proceeds earmarked for families affected by the typhoon in the Philippines and a tornado in Indiana, Torp said.

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Officials at the scene held back a childhood friend of Walker's from trying to take the actor's body from the burning car, and firefighters had to pull Rodas' young son away from the wreckage, Torp said.

"They just didn't want to believe this happened," Torp told fans and media at the crash site Sunday. "It was 'Fast and the Furious,' that's what it is. Both race car enthusiasts, both loved speed, both knew how to handle cars, and this had to happen."

Sheriff's officials said speed may have been a factor in the crash, which occurred on a quiet street with a 45-mph limit. The car knocked over a tree and a concrete lamp post. The cause of the crash remains under investigation, sheriff's Deputy Kim Manatt told The Times.

The smell of the burned Porsche lingered in the morning air as fans set up a makeshift memorial at the crash site on Hercules Street, near Kelly Johnson Parkway. "Fast and Furious" memorabilia were placed alongside candles and flowers. One sign read, "Paul Walker Race in Heaven."

Walker has several other pictures already shot, and Saturday's news had those films' distributors contemplating their options.