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.