Finally, a voice came over the arena PA: "Security, please clear the arena."

The assembled musicians again ran through their medley of Stone hits and then ... there he was, in a hooded, camouflage rain slicker, matching pants and 3-inch platform boots. He came to a keyboard at center stage and made eye contact with no one. Still lean, but beneath the hood he seemed smaller than he was in the '60s.

The teleprompter told him how to reintroduce himself to the world: (SLY): Ow Ow Ow.

He sang "I Want to Take You Higher," and his voice was robust and clear. Looking straight down, his chin bounced on his chest. His left hand and wrist were in a cast. From under the hood, he peeked at the musicians next to him, grinned ... and then he was gone. Adam Levine stared at the long lost star like was a museum piece. Perry, beneath a black cowboy hat, smiled and shook his head.

Legend gave the first review of the performance: "It was great — I mean, hey, he showed up."

Afterward, John Cossette, executive producer of the show, looked a bit ashen. Stone sounded great, no doubt, but he also looked a bit ... nutty. "No comment. He's not doing this, he's not hiding out for 15 years to do what you just saw."

He was right. Stone came back and did it again. This time, his plastic pants were tucked into his boots and, at the song's close, he stepped away from the keyboard, bobbed his head and beamed. And then he was gone again.

Ehrlich, like a man who wants to recheck his lottery ticket, called for a third run-through. This time, though, when it came to the point where Stone should have dashed out on stage, there was a long lull and empty air. Finally, a crew member jumped up behind the keyboard and played the part of the enigmatic star.

Two out of three is good — unless the third one is live on the air in front of the world. But maybe it doesn't matter. Young R&B star Van Hunt said afterward that, on stage or not, Stone is a presence. "When he came out, I have to tell you, I didn't even look at him. I couldn't. I mean, it's Sly. I was afraid to look. I don't even think the guy is real."