From the 1985 film Back to the Future:

George McFly was "birdwatching" outside Lorraine Baines' house, when he fell out of his tree and was hit by Mr. Baines' car. Mr. Baines took him inside, while Lorraine took care of him. She felt bad for him, and so asked him to the "Enchantment Under the Sea Dance". Eventually, they got married.

When Marty went back in time, he screwed this up by pushing George out of the way and getting hit himself. Lorraine took a liking to her future son, who then had to convince George to not only ask Lorraine to the dance, but to make himself look like a "real man" while doing it.

At the dance, Marty arrived with Lorraine, but had to take over for the band's guitarist after he sliced his hand trying to get Marty out of Biff's trunk.

Meanwhile, George started dancing with Lorraine until one of Biff's goons cut in. Eventually George screwed up his courage enough to push the chucklehead out of the way, SAVING THE FUTURE AS WE KNOW IT.

I hate to be picky, (not really) but I always remember the Professor calling it a "rhythmic ceremonial mating ritual." (?) It always cracks me up when I am watching Back to the Future for the Nth (where N is a number greater than 15) time on the USA network. Then later I rock out as Marty rips off Pete Townshend and Chuck Berry to stun and horrify the horribly square high school kids. Then I get a little warm glow as George finally gets the girl. But enough kibitzing...