In his first speech since a gunman tried to kill him, Donald J. Trump stood before an arena of supporters and began, simply, with what he knew they wanted to hear.

He told the tale.

It was a theatrical, dark and, at times, quasi-religious retelling. Mr. Trump spoke slowly, paused purposefully, and even re-enacted the way he had turned his head just as a would-be assassin’s bullet sliced through his ear.

He would eventually slip into a version of his familiar stump speech, and the drama dissipated. But for those first 15 minutes, the former president delivered a campaign speech like no other — a remarkable narration of a near-death experience packaged as slick political theater.

And he knew how to hype it, telling his audience at the top that it was a one-night only, special event. “So many people have asked me what happened, ‘Tell us what happened, please,’” he said. “And therefore, I will tell you exactly what happened, and you’ll never hear it from me a second time. Because it’s actually too painful to tell.”

He began. “It was a warm, beautiful day in the early evening,” he said, and his campaign “was doing really well” and “everybody was happy” and he was “speaking very strongly, powerfully, and happily.”