(FORTUNE Magazine) – Considering Scott Sassa's career, you might think his main talent is failing his way to success. He got fired from Fox Broadcasting by Barry Diller, squeezed out of Time Warner by Ted Turner, and nearly knocked out cold when the company he headed for Ronald Perelman crashed into bankruptcy. But he's rebounded each time. He's like a pole vaulter who misses the bar and then says, "Raise it higher, please."

Now Sassa is in a job in which failure may well be inevitable. As the new president of NBC Entertainment, he is supposed to turn around General Electric's once invincible broadcast network--and he's taking over just as NBC's schedule is collapsing and viewers continue to flee the broadcast networks for cable. "This is a thankless job," says Sanford C. Bernstein analyst Tom Wolzien. "They're saying to Scott, 'Here, the network is tanking. Have a nice day.' "

Sassa is fascinating because he's managed to align himself with legendary bosses and catapult ahead, even when he fails at a job. His secret? "If you're in the right place and do bad work, you get more attention than if you're in the wrong place and do good work," he says. "The karma at the hot place is powerful."

Sassa, 39, has been successful because he bowls over great bosses who love risk enough to let him fail. Those bosses seem to agree with that assessment: "Scott is brilliant," says Ted Turner, who hired Sassa twice to help him build his cable empire. "He's a networker in the best sense," says Ron Perelman, who knows a good schmoozer. "He's savvy. He's got very good instincts. Firing Scott was one of my supreme mistakes," says Barry Diller. Sassa is so impressive at first meeting that Jack Welch says, "I never interviewed anyone I liked more." (Really? "Never," the GE chairman insists.) Sassa is so ambitious that in his first week at GE, he surprised NBC chief Bob Wright with a high-tech presentation on the future of television--a little show he'd thrown together over his summer break.

Like most unlikely success stories, Sassa's begins with a troubled past. A third-generation Japanese American from the Los Angeles suburbs, he got kicked out of high school for smoking pot. ("He deserved it," says his mother.) He dropped out of the University of Southern California (where he was a cheerleader) a few credits short of a degree. At 23 he went to work for Ted Turner and launched the Cable Music Channel, an MTV rival. It failed. "I thought I'd never work again," Sassa says. Of course, he did work again, joining Barry Diller at the startup of Fox Broadcasting. He got fired the next year. He was in over his head, says Diller.

Sassa finally scored at Turner Broadcasting the second time around. Ted Turner had decided to create entertainment networks (and loathed the necessary hobnobbing in Hollywood). Sassa was his ambassador. When Turner promoted him to president of Turner Entertainment, Sassa executed the boss' ideas--TNT, Turner Classic Movies, the Cartoon Network--with unflagging tenacity. But in 1996, when Turner sold his company to Time Warner, Sassa lobbied so brashly to be his second-in-command that he alienated some colleagues. Turner chose veteran Terry McGuirk instead. Nevertheless, Turner sticks up for Sassa: "Scott is good at self-promoting, and there's nothing wrong with that. He wants to get to the top. I wanted to get to the top too."

Life near the top hasn't been easy since. Sassa fled Turner and took the CEO job at Marvel, but six weeks into his tenure, the trading-card and comic-book company collapsed into bankruptcy. Once again, failure didn't damage Sassa. "Scott was a champ," says Perelman, who was Marvel's biggest stockholder. "He could have quit, but he stuck with it and proved himself a real standup guy."

Sassa landed at GE in late 1997. He started in what might be considered the engine room of NBC, its high-profit and low-profile local TV stations, but he rose fast: After NBC lost Seinfeld and 18% of its audience last fall, Bob Wright said goodbye to longtime programmer Warren Littlefield and replaced him with Sassa. Sassa has never actually developed a TV show, but Wright says that may be an advantage. "We have to break away from the traditional network-type show," he says. "We need breadth."

So now Sassa is stretching his talents again. He must pick some hits for next season, hire an experienced programmer (probably Garth Ancier, who recently left the WB network), and smooth relations with the studios, which are fighting NBC over program ownership. Before year-end, Sassa is due to replace Don Ohlmeyer, the broadcast network's top executive, and then he'll face his big challenge. While NBC, including the stations and cable, is healthy overall, the broadcast business is so lousy today that the NBC network is the only one that earns a profit. In fact, Wright predicts that NBC is the only one that will ever make money.

Sassa, of course, is charged by that doomy prediction. "There's so much tenacity at GE," he says, ever the cheerleader. "The attitude is, 'You can make money. You will make money.' " As for Welch, he has high hopes for Sassa. GE's chief says he doesn't want to sell NBC but rather "make it better. We need more complicated business relationships. Scott can do that. He has a lot of runway to do a lot of things."

--Patricia Sellers