There was a time when Mitt Romney was known for pranks. When a schoolyard crush married someone else, he painted the groom’s leather shoes with pink nail polish so when he knelt at the altar it would show. Then there was the time he dressed up as a police officer, put a flashing red light on the roof of his car and chased after two buddies while they were on a double date.

Former Massachusetts Gov. Mitt Romney (R) jokes with Rep Paul Ryan (C) (R-Wis.) and Sen. Ron Johnson (R-WI) during a pancake brunch at Bluemound Gardens on April 1, 2012 in Milwaukee, Wisconsin. (Justin Sullivan/GETTY IMAGES)

But when his aides orchestrated an elaborate prank for him on Sunday, Romney was befuddled. He had forgotten it was April Fools’ Day. And on this morning, as he recounted to a crowd here, “they turned me into the April fool!” Luckily, the scene was caught on video.

The Republican presidential front-runner was all set to deliver a stump speech at a pancake breakfast in Milwaukee. He was ushered into a ballroom. He waited backstage behind a black curtain. Arrows on the floor showed him where to walk.

An aide warned Romney that, for whatever reason, turnout was low but that he would have to power through the event. “It’s really small,” one aide said, “but it will be okay.”

Rep. Paul Ryan (R-Wis.) went out first to introduce Romney, “the next president of the United States!” Romney could hear applause, and when his intro music, Kid Rock’s “Born Free,” blared from the speakers, he and Sen. Ronald H. Johnson (R-Wis.) walked out from behind the black curtain.

“It’s completely empty!” Romney said, save for a handful of aides. “There’s nobody there. I thought, ‘Oh, boy, this is gonna look really bad on the evening news, let me tell you.’ ”

It turned out that Ryan and Johnson were in on the prank, which Romney’s traveling aides had hatched up late Saturday night. They had built a fake set for a Romney event. The applause was really a soundtrack played through a set of speakers.

“So not only did they do that, but they caught it on camera,” Romney said. “You guys — this is known as ‘forgive but remember,’ I’ll tell ya. We’re gonna remember this.”

After aides shouted “April fools!” at him, the former Massachusetts governor made his way to the real ballroom, where he addressed an overflow crowd of several hundred supporters and served them pancakes.