Relative to many of its ruined rivals, ­Deutsche Bank enjoyed a “good” financial crisis. It lost billions, but it had also placed market bets that anticipated the housing crisis, and the resulting profits largely made up for other losses. It was one of the few major international banks that seemed strong enough to avoid a direct government bailout, and many investors were pacified by the knowledge that if things got really dicey, the German government would come to the rescue.

For a brief spell, ­Deutsche Bank was the toast of the financial world. Within a few years, though, it had become one of the industry’s leading problem cases. The crisis — and the waves of new regulations that came afterward — fundamentally changed Wall Street. ­Deutsche Bank’s business model had hinged on making enormous wagers with borrowed money; in essence, the one-time icon of German sobriety had become a giant casino. Now this proprietary trading was outlawed in the United States. Regulators around the world — deeply suspicious of the sort of adrenaline-­crazed, rule-­bending tactics that had come to define ­Deutsche Bank — also pushed banks to lessen their reliance on borrowed funds.

Cocky from their performance during the crisis, ­Deutsche Bank executives initially refused to do so. Nor did they use this moment of relative strength to rid the bank of the mountains of unwanted assets — in particular, trillions of dollars’ worth of derivatives that had the potential to saddle the bank with enormous losses — that were polluting its balance sheet.

One of the few concessions the bank did make to the new era was to start looking for safer ways to earn money. One was private banking: providing personalized services to the richest of the American rich. To differentiate its then-­sleepy private-­banking division from the competition, ­Deutsche Bank planned to work with customers who were untouchable for rival banks and to do deals that were too risky or too complicated for others to stomach — a variation on the strategy that Offit and Kennedy’s squad had deployed a decade earlier when trying to get the commercial real estate business off the ground. And no one was more central to that project than a woman named Rosemary Vrablic.

Vrablic grew up in the Bronx and then the New York City suburb of Scarsdale and started out as a bank teller before eventually landing a job analyzing proposed loans. In 1989, a headhunter recruited her for a job in Citicorp’s private-­banking arm. Citi was widening its suite of offerings to such clients, including by making loans to finance their big real estate projects. She quickly took advantage of this new lending service to become one of New York’s leading bankers to the superrich, first at Citi and then at Bank of America. Vrablic specialized in dealing with difficult men. “They’re successful, and they’ve earned their money by being tough,” she explained in an interview years later. “So I don’t have a problem with tough.” One of her youngest clients was Jared Kushner, who was taking over his family’s real estate company.

In 2006, Vrablic met Tom Bowers, who had joined ­Deutsche Bank the year before with a mandate to help the German bank make a name for itself among ultrawealthy Americans. Vrablic, who was 46 at the time, soon agreed to join ­Deutsche Bank, with a guaranteed salary and bonus of at least $3 million a year. She started bringing in tens of millions of dollars in annual revenue for the bank. Bowers told me she was by far the top producer in the bank’s New York offices.

The litigation between Trump and ­Deutsche Bank over the loan for his Chicago skyscraper was settled in 2010, with the bank agreeing to give Trump two years to make good on his obligations, including the $40 million that he had personally guaranteed. And if he wanted to keep expanding his empire, he would need to identify a new source of credit. The trouble, as ever, was that serious banks wouldn’t get anywhere near him. Even ­Deutsche Bank, it seemed, was now off-­limits after the Chicago fight.