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1. Dumb and Dumber was Peter Farrelly and Bobby Farrelly's first movie—and it was a true labor of love. Years beforehand, Peter and his friend and frequent writing partner Bennett Yellin wrote a screenplay about two not-very-bright funeral home employees, which was eventually bought by Eddie Murphy's production company. Unfortunately, there it languished.

Joined by Bobby, the trio wrote Dragnet 2, a sequel for the 1987 comedy with Tom Hanks and Dan Aykroyd, "our best script," Peter told an audience at Loyola Marymount's School of Film and Television in 2014. However, that didn't get made, either.

Back at the drawing board, the Farrellys and Yellin came up with another story, this one about dim-witted buddies Harry and Lloyd, who set off for Aspen to return a lost briefcase to its wealthy owner. They called it Go West, then A Power Tool Is Not a Toy. "We changed the titles because we couldn't get agents to deliver a script called Dumb and Dumber to their clients," Peter said.