When the red phone at the Continental Air Defense System rang in December of 1955, Col. Harry Shoup knew it was important.
Turns out, it was more important than any call he'd ever receive, and had nothing to do with the military or missile defense. The call would set in motion a tracking of Santa Claus that has thrilled millions of children ever since.
Shoup was in the control center of the U.S. radar defense system deep in Colorado Springs, Colo. It was the height of the Cold War with the Soviet Union, a time when many Americans built bomb shelters in their backyards and the dark years of the Korean War and McCarthyism had only just passed.
The red phone was in the Block House, which had no windows. The phone was reserved for the Pentagon and a four-star general, so Shoup answered the phone on full alert.
"I picked it up and said, ‘Yes sir, this is Col. Shoup,'" he recalled in an interview before his death at the age of 92 in 2009.
There was silence on the line.
"Sir? This is Col. Shoup?" he said.
"I said, ‘Sir, can you read me all right?'"
At that point, a small voice came through the line with a simple question: "Are you really Santa Claus?"
"I looked around at my staff and thought, ‘Somebody is playing a job on me, and this isn't funny.'"
"I said would you repeat that, please?"
And again, the boy asked, "Are you really Santa Claus?"
"I knew then," Shoup recalled," there was some screw-up in the phones."
Incredibly, he decided to play along.
"I said, ‘Yes I am. Have you been a good little girl?'"
The girl had a long list of requests, and Shoup said, "I'll talk to your mother and tell her she better get you everything on that list."
Shoup, in talking to the mother, learned a stunning fact – that day, Sears Roebuck had run a big advertisement in the local paper with a bold headline: "Hey, Kiddies, Call me direct on my telephone. Just dial ME 2-6681."
Turns out, there was a typo in the ad, and the number that was printed was the secret line to the red phone.
Shoup told his staff to play along as the phone calls kept coming in. Eventually, they had the idea to say that they were tracking Santa Claus on the radar.
And from there, the project exploded. The Continental Air Defense System is now called NORAD, and this past Christmas, the Santa Claus program logged 19.58 million unique visitors to its website on Christmas Eve, according to the Associated Press.
NORAD said Thursday that volunteers answered 117,371 calls from children seeking information on Santa's whereabouts. First lady Michelle Obama was among the program's 1,200 volunteers.
An additional 146,307 followed Santa's progress on Twitter. The program also got 1.45 million "likes" on Facebook.
And it all happened because of a typo in a newspaper ad – and a colonel's willingness to play along when a child tapped into one of America's top-secret phone lines.