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So THAT's what happened.

In his first interview since the infamous invisible Obama empty chair routine that transfixed the Republican National Convention last month, Clint Eastwood tells the newspaper in Carmel, Calif., that the Romney campaign didn't know what he was going to say and he didn't come up with the empty chair idea until he was about to go on stage.

"They vet most of the people, but I told them, 'You can't do that with me, because I don't know what I'm going to say,'" Eastwood told the Carmel Pine Cone.

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He came up with the idea to interview an absent Obama just before taking the stage.

"There was a stool there, and some fella kept asking me if I wanted to sit down," Eastwood said. "When I saw the stool sitting there, it gave me the idea. I'll just put the stool out there and I'll talk to Mr. Obama and ask him why he didn't keep all of the promises he made to everybody."

The only person he told about the idea was the stage hand.

"The guy said, 'You mean you want it at the podium?' and I said, 'No, just put it right there next to it.'"

Eastwood said he's not used to giving speeches, but in his estimation, that was supposed to be part of his draw for independent voters that might be watching.

"It was supposed to be a contrast with all the scripted speeches, because I'm Joe Citizen," Eastwood said. "I'm a movie maker, but I have the same feelings as the average guy out there," he said.

Check out the entire interview from the Carmel Pine Cone .

Watch Eastwood's empty chair speech: