Donald Trump had come to a run-down New York City apartment on an autumn day in 2003 to tape a scene for his new reality television show, The Apprentice. Suddenly, one of the contestants cried out in surprise.

The young woman, Omarosa Manigault, had been struck in the head by a piece of plaster dislodged from the ceiling by a microphone boom. She immediately blamed the mishap on another contestant. As Trump watched, every camera in the room shifted to capture the outburst, one of those moments that are the lifeblood of reality television, a former crew member recalled.

Fast-forward to 2016: as a presidential candidate, Trump talks often about turning the cameras. He creates moments of great drama during his rallies by pointing out television cameramen and accusing them of refusing to show the size of his crowds.

“Turn the camera!” he chanted at a Michigan rally last year. The crowd of 9,000 joined him until a roar filled the room and exploded into cheers as the cameraman finally swung his camera to show the crowd. Such scenes have become commonplace.

Trump’s 2016 White House run is built in part on drama and controversy, a campaign that former cast and crew members of The Apprentice said appeared to draw lessons from reality TV, especially one: how to grab the public’s attention and keep it.

Trump denied in an interview that he had learned any tricks from the show. His success on television, he said, came from a “natural instinct”.

But those involved in The Apprentice said Trump the candidate is not all that different from the contestants on the dog-eat-dog elimination game show, where 14 people engaged in a series of business-related challenges to win a job at Trump’s real estate company. At the end of each episode, Trump would appear with the contestants in an executive boardroom and eliminate one with his trademark “You’re fired”.

A producer on the show’s first season, Bill Pruitt, said he believed Trump had learned, by watching and refereeing fights among the contestants, how they “defended or went after one another”. Pruitt said he had seen Trump evolve on the show, honing his ability to get candidates to turn on one another, one of the hallmarks of the show.

“He learned, as time went on, how to do that, how to speak and create reactions,” said Pruitt, who is not supporting Trump’s presidential run.

“The campaign is much different than a show,” Trump responded, rejecting the idea that his campaign bore any resemblance to reality television.

The Apprentice gave him a truly national platform for the first time and he saw how his blunt and unfiltered style helped make the show a major hit

Long before the debut of The Apprentice, the New York businessman was a regular fixture in the pages of his hometown’s daily newspapers, which covered his fights with other real estate developers and celebrities like Rosie O’Donnell.

But The Apprentice gave him a truly national platform for the first time, and he saw how his blunt and unfiltered style helped make the show a major hit. At it’s peak, nearly 21 million people watched the show, which ran for 14 seasons and has still not been cancelled by NBC.

“I haven’t changed. The Apprentice didn’t change me. I think I changed The Apprentice,” Trump said, asserting that he had come up with the idea to say, “You’re fired.”

And he dismissed intensifying criticism that his presidential campaign thrives on conflict. “I’m not looking for conflict. With the show it’s a little bit different.”

Yet Trump has dominated media coverage of the election in a way that has little modern precedent in American politics, and he has done that mostly by saying or doing something that makes people angry.

His barrage of insults in Twitter battles with opponents, including fellow Republican candidates, has delighted many supporters, who regularly tell pollsters they like the billionaire because he says what he thinks and doesn’t hold back. His claim that Mexico was sending rapists over the US border enraged the Mexican government; his call for a temporary ban on Muslims entering the US prompted widespread international condemnation, as did his call for killing the families of terrorists and for torturing terrorism suspects.

Mike DeMatteo, who worked on The Apprentice as a sound mixer for nearly a decade, said it would have been hard for Trump not to have drawn lessons from the show.

“When you’re sitting back and watching it and seeing the reaction in the press as it evolved, you get a very good gauge of what people are talking about, who they like, what they don’t like,” he said. “You’re really starting to understand the people out there.”

DeMatteo described himself as a Trump fan but said he disapproved of some of his recent comments.

The place where Apprentice contestants could battle for fame was the boardroom. Boardroom scenes found Trump seated at the head of a long polished wood table, criticising contestants’ work. Contestants worked in teams, so Trump’s questions were often about which team member was to blame for mistakes.

“He would ask a lot of very to-the-point questions, he would put people on the spot, he would get information about contestants that would make the other ones mad at them,” recalled DeMatteo.

Michael Tarshi, 36, a Boston-based real estate developer and a contestant has first-hand experience of this.

During one boardroom scene in the third season of the show, Trump listened as members of a team described their roles in a failed project. Trump then asked one of the members, Bren Olswanger, whom he would fire. Olswanger named team-mate Stephanie Myers, setting off an argument between the two contestants.

When Tarshi tried to interject, Trump cut him off: “Michael let me ask you a question. He’s telling me how bad Stephanie is and you’re interrupting him with nonsense over nothing. Let me ask you this: He’s killing her. He’s going after her. She should be fired according to him.”

Trump then turned the tables on Tarshi. “Michael, you’re fired,” he said.

“He definitely learned a lot about how to manoeuvre, to incite conflict between each contestant and each political candidate,” said Tarshi, who has attended Trump’s rallies and private parties promoting his presidential bid.

The most popular season of The Apprentice was its first, in which Manigault was struck by the plaster.

Even though that scene never aired, Manigault spent several episodes complaining about being hit on the head. It helped define her as the show’s combative character – a role that made her famous and fueled the show’s popularity.

She has remained a public figure and has endorsed Trump for president. In praising her combativeness at a rally last month, Trump could have been describing himself.

“When Omarosa goes after you, you’ve gotta be quick – boom boom – and you’ve gotta be fast,” he told the crowd.