But, according to the actor, like his famed How I Met Your Mother character Barney Stinson, he had a few tricks up his sleeve. "I love games and puzzles and stuff, so it was all these surprises, no one kind of knew what was happening as it was going on," Patrick Harris said of his sweet celebration. "We started dancing to ["A Moment Like This"] and we had a plan: We had a firework guy, who, when the song crescendos, fireworks were supposed to go off." But, because they were in a small town in Italy, Patrick Harris didn't have faith that it would occur "at 2:27 like at Disneyland." To his delight, "It happened perfectly."
Photos: Courtesy of Late Show with David Letterman
After showing a few snaps from that spectacular moment, Letterman and Patrick Harris said together: "Take that, Clooney!" Watch the entire interview, above!