The most frenzied American ritual you’ve never seen is called the “transfer of families,” a five-hour tsunami of activity that transforms President Obama’s home into President Trump’s.

“I call it organized chaos,” said Gary Walters, who choreographed several transfers of families in his 21 years as the White House chief usher.

“It’s energizing,” said Ann Stock, who saw the transfer up close as the Clintons’ social secretary, “but absolutely exhausting.”

Here’s what happens on Inauguration Day before and during those five hectic hours.

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