The scheme would unfold Thursday, with the only uncertainty being Mubarak’s fate. “There were two scenarios: He would either leave office, or he would transfer power,” said a U.S. government official who was briefed on the plan. “These were not speculative scenarios. There was solid information” and a carefully crafted script.

But the Egyptian president decided at the last minute to change the ending.

“Mubarak called an audible,” the official said…

In the end, Mubarak’s efforts only ensured a hasty and ignominious departure, the officials said. Within hours of the speech, Egyptian army officials confronted the discredited president with an ultimatum: Step down voluntarily, or be forced out…

“Mubarak went off script,” Carpenter said. “But it wasn’t what he said so much as it was the way he said it. He essentially agreed to say everything the army wanted him to say, but he couldn’t say it the way people expected him to.”