Dr. Puliafito resigned as dean about a week later, saying he wanted to pursue outside opportunities, but he remained on the faculty, continued to see patients and was honored at a reception on the lawn of the medical campus that June. “Carmen’s proven business expertise meshed perfectly with his superb medical skills,” Dr. Nikias said at the time. “He brought a new generation of exceptional clinical leaders, department chairs and world-class talent to our campuses.”

Only now, after the exposé, did the university move to dismiss him entirely.

By every measure, the case is far from over. Ms. Yang has just started her investigation. There are concerns that Dr. Nikias, 64, the university president since 2010, can be forced to step aside if U.S.C. is found to have ignored damning information about Dr. Puliafito. The videotapes mentioned in the Los Angeles Times article, including one in which Dr. Puliafito is said to be seen popping an orange ecstasy tablet, according to the newspaper, could end up leaking as the investigation continues, providing graphic evidence of behavior that so far has only been described.

The university’s efforts to recast its reputation — it was commonly referred to as the University of Spoiled Children — began under Dr. Nikias’s predecessor, Steven B. Sample, who served as president for 19 years. He began fund-raising aggressively so the school could build extensively, recruit (some critics preferred the word “raid”) top-notch faculty members and researchers from other universities and help pay for scholarships to attract more minority students.

“I don’t think it’s going to materially affect the school,” said Dr. David Warburton, a professor of pediatrics at the medical school. “Having said that, this is not good for morale in the short term.”

While much of the focus was on biomedicine, the university also expanded its media and political offerings, which served to raise its profile even more. Arnold Schwarzenegger, the former Republican governor, opened the Schwarzenegger Institute for State and Global Policy there. The George Lucas Family Foundation began a $20 million endowment to support black and Latino students at the university’s film school. The music moguls Jimmy Iovine and Dr. Dre gave $70 million to create a degree that combines business, marketing, design and liberal arts.

This year, the university received a record 56,000 applications and has a 16 percent acceptance rate, compared with 23 percent in 2011, reflecting the increasingly competitive environment. The number of instruction faculty jumped to 3,455 from 3,123 during the same period.

“It’s a pretty popular school with our kids,” said Ed Graf, director of college counseling at Isidore Newman School, an independent school in New Orleans. “Twenty-five years ago, most of our kids would have gotten into U.S.C. Nowadays, it’s risen up the ranks in competitiveness a lot.”