The penthouse felt less like a home and more like a high-security prison after Alexander’s devastating discovery in the foyer. The letter from R.V. Holdings—the formal demand for nearly nine million euros, backed by a mobster and aimed at a Manhattan court—was now sitting on Alexander’s desk in his office, the silent epicenter of the gathering storm.

Alexander had left right after his cold, silent command, heading back to his office downtown to "mitigate the legal exposure." But I knew ...