“Glen-Richard . . . he kills like other men pick food from their teeth. Since the Volstead Act came in, he’s flooded the city with toxic homemade liquor, and we don’t even know where he is. We locked down every bridge, every tunnel, every river, every airfield. We raided warehouses, factories, apartment buildings, boxing gyms, gentleman’s clubs, nickelodeon houses, Broadway theaters, and anywhere else big enough to hold a still. Even in my wildest theories, I could not have guessed at anything like this.”

“No sane man could. That’s where you and my father differ. Why do you say ‘we raided’?”

“It’s my investigation, isn’t it? I wouldn’t be much of a cop if I let the uniformed men have all the fun of breaking down doors.”

Now I was the one too stunned to ask questions. Virgil Carr, king of the NYPD, had never fallen from his throne.

We walked back toward Washington Square, and the detective’s curiosity flared. He asked plenty of questions now—not about the case that had brought me here, but about Virgil and Mary Fall. He wanted to know everything, from where they had spent their last vacation to the precise shade of my mother’s eyes. I improvised as best I could, hiding the truth not because I didn’t trust him, but because I had long ago tired of the look—a flickering of pity, embarrassment, and disgust—that people give when they learn your parents are dead.

We were two blocks from the park when he told me I was lying.

“And just how would you know that?” I said.

“Two years ago, I got a call from a friend who works the river. A couple of kids in Italian Harlem were playing on what passes for a beach up there, and they found what they thought was a cabbage floating in the water. Only it was a cabbage with gray hair, thick sideburns, and a three-inch chunk of spinal column hanging from the neck. When my friend heard my voice, he could hardly talk. ‘I was so worried, Virgil,’ he said. ‘I thought it was you.’ That must have been your father’s head.”

A vanishing isn’t a death. It’s just a question, left forever unanswered, that hangs in the air like mustard gas: “When are you coming home?”

Two years later, I had my response, and it came in my father’s voice: “Never, never, never.”

Suddenly, I was sitting on a bench. I didn’t remember how I got there, or when Virgil pressed his handkerchief into my hands. It took a long moment before I was able to speak.

“It was September 7, 1919, that he disappeared,” I said. “There was a . . . my god, there was an item in the Sentinel the next day. I read it, and it didn’t even register.”

“What did it say?”