As one of the most prolific directors in Hollywood, Tony Scott's death leaves a quartet of high-priority projects in limbo.

Among them was the anticipated sequel to the 1986 blockbuster "Top Gun" that became a cultural touchstone and launched Scott's Hollywood career.

It had taken years to get the movie even close to being made due to the complexities of reuniting Scott with star Tom Cruise and producer Jerry Bruckheimer on a concept all three would endorse. The picture was to focus on the world of drones in modern aerial combat.

Its backers, Paramount Pictures and Skydance Productions, had hoped to start shooting the sequel early next year and release it in theaters in 2014.

There were three other projects also vying to get Scott behind the camera this coming winter.

But, the day after news of Scott's apparent suicide spread throughout Hollywood, none of the studios behind these endeavors had any clue how and whether to proceed without the filmmaker who had championed them.

The other films on Scott's to-do list were "Narco Sub," about the underwater transport of drugs from Latin America to the U.S.; "Lucky Strike," about a DEA agent forced to run a mission with a drug dealer which potentially was to star Mark Wahlberg and Vince Vaughn; and a remake of Sam Peckinpah's 1969 western"The Wild Bunch."

Those involved in his pending projects said there was no sign in the last several weeks that the 68-year-old Scott's energy for filmmaking was flagging or that he was suffering from the kind of depression that could lead to suicide.

"We had a meeting just two weeks ago and he was burning with the excitement of creating stuff," said Tom Rothman, chairman of 20th Century Fox, the studio behind "Narco Sub" and "Lucky Strike."

Adam Kolbrenner, who manages "Narco Sub" screenwriter David Guggenheim, painted a picture of a filmmaker who continued to throw himself into his work, adding that there had been "no hiccup" in communication between Scott and the principals on the project at any point over the last few months.

Bruckheimer, who has collaborated with Scott on six films including "Top Gun," declined to be interviewed about Scott and the fate of "Top Gun 2." On Friday, the producer traveled with Scott and Cruise to the naval air station in Fallon, Nev., 70 miles east of Reno, according to a public affairs officer at the base.

PHOTOS: Director Tony Scott dead at 68

During their half-day visit, they met with the commanding officer and talked to other officials to learn more about the modernU.S. NavyStrike Fighter Tactics Instructor program, more popularly known as TOPGUN.

In a prepared statement, Bruckheimer said Monday, "I was shocked and devastated to learn of Tony Scott's death. He was not only a brilliant filmmaker but a wonderful man and dear friend. He was thoughtful and warm and had an irrepressible sense of humor. I was fortunate to have worked with him for 30 years … Tony was a true original and he will be terribly missed by everyone who knew him."

It is also unclear what will become of "Narco Sub," a movie Scott had been developing with Guggenheim, the writer of this year's crime drama "Safe House," starring Denzel Washington. For the last eight months, Scott and his producing partner on the film, Simon Kinberg, had been working to refine Guggenheim's script.

"He'd worked out the human story, and now he was working on the machines," Kolbrenner said.

The fourth planned endeavor on Scott's slate was a remake of director Sam Peckinpah's "The Wild Bunch," the 1969 western that starred William Holden and Ernest Borgnine. It was being written by Brian Helgeland, who previously worked with Scott on the movies "The Taking of Pelham 123" and "Man on Fire" and won an Oscar for 1997's"L.A. Confidential."

It remains to be seen if other directors will step in and continue Scott's work on any of the projects. Sometimes the death of a key player makes it impossible for movies in development to continue.

In similar instances, it is not unprecedented for another filmmaker to pick up the mantle, as Steven Spielberg did on the movie "A.I." after director Stanley Kubrick's death in 1999.

Scott's presence will also be felt on screen next year when Relativity Media releases the recently wrapped film "Out of the Furnace," a dark drama about an ex-con on the run in Indiana that the director and his older brother Ridley Scott helped put on the map when they bought a script from a Pennsylvania insurance salesman four years ago and decided to produce it.

The Scotts' production company Scott Free also helped oversee "Stoker," the English-language debut of South Korean auteur Chan-wook Park. Fox Searchlight will release the film March 1.

In recent years, Scott, who began his career as a top commercial director, also found a large canvas on the small screen with such hit CBS television series as"The Good Wife," which some critics have called the best drama on television, and "Numb3rs," which ran six seasons before ending two years ago.

On Labor Day, A&E plans to unveil a four-hour, two-night legal thriller titled "Coma," co-produced by the Scott brothers and Sony Pictures Television.

Shooting on the Scotts' documentary "Killing Lincoln," based on the bestselling book "Killing Lincoln: The Shocking Assassination That Changed America Forever" by Bill O'Reilly and Martin Dugard, wrapped up earlier this month in Virginia and is expected to run next year on the National Geographic Channel.

"The Drivers," another project in development with Sennet Entertainment but not set up at a network, is expected to be a 13-episode-a-year ongoing series based on the true-life stories of adrenaline-charged young drivers in the early and dangerous days of Formula One racing in Europe.