It remains one of the most enduring mysteries in gangland lore: in 1941, while Abe Reles and three other key informants were under round-the-clock NYPD protection, the ruthless and powerful thug took a deadly plunge from the window of a Coney Island hotel. The first criminal of his stature to break the underworld’s code of silence, he had begun “singing” for the courts—giving devastating testimony that implicated former cronies—with more to come. With cops around him day and night, how could Abe have gone out the window? Did he try to escape? Did a hit man break in? Or did someone in the “squealer’s suite” murder him? Here’s the gripping story, packed with political machinations, legal sleight-of-hand, mob violence—and, finally, a proposed answer to the question: How did Abe Reles really die?