The magician didn’t answer for a moment. Then he opened one eye. “No,” he said slowly, “not just yet.” He took his feet off the desk and sat up straight. “You know,” he said, “if we don’t accept the theory of the murderer from beyond, then Ross must be right after all. Elinor Drake’s statement to the contrary, there must have been a third person in this room when that séance began.”

“Okay,” Gavigan said, “we’ll forget Miss Drake’s testimony for the moment. At least that gets him into the room. Then what?”

“I don’t know,” Merlini said. He took the roll of gummed paper tape from the desk, tore off a two-foot length, crossed the room, and pasted it across the door and jamb, sealing us in. “Suppose I’m the killer,” he said. “I knock Rosa out first, then stab Drake—”

He paused.

Gavigan was not enthusiastic. “You put the murder knife in your pocket, not noticing that the point is broken. You put blood on the paper knife to incriminate Rosa. And then—” He waited. “Well, go on.”

“Then,” Merlini said, “I get out of here.” He scowled at the sealed door and at the window. “I’ve escaped from handcuffs, strait jackets, milk cans filled with water, packing cases that have been nailed shut. I know the methods Houdini used to break out of safes and jail cells. But I feel like he did when a shrewd old turnkey shut him in a cell in Scotland one time and the lock—a type he’d overcome many times before—failed to budge. No matter how he tried or what he did, the bolt wouldn’t move. He was sweating blood because he knew that if he failed, his laboriously built-up reputation as the Escape King would be blown to bits. And then. . .” Merlini blinked. “And then. . .” This time he came to a full stop, staring at the door.

Suddenly he blinked. “Shades of Hermann, Kellar, Thurston—and Houdini! So that’s it!”

Grinning broadly, he turned to Gavigan. “We will now pass a miracle and chase all the ghosts back into their tombs. If you’ll get those people in here—”

“You know how the vanishing man vanished?” I asked.

“Yes. It’s someone who has been just as canny as that Scotch jailer—and I know who.”

Gavigan said, “It’s about time.” Then he walked across the room and pulled the door open, tearing the paper strip in half as he did so.

Merlini, watching him, grinned again. “The method by which magicians let their audiences fool themselves—the simplest and yet most effective principle of deception in the whole book—and it nearly took me in!”

Elinor Drake’s eyes still avoided the stains on the floor. Scott, beside her, puffed nervously on a cigarette, and Dr. Garrett looked drawn and tired. But not the irrepressible Potter. She seemed fresh as a daisy.