"Back to the Future" celebrates 30 years

This year marks the 30th anniversary of the release of "Back to the Future," the classic sci-fi comedy starring Michael J. Fox and Christopher Lloyd.

"Back to the Future" was the highest-grossing film of 1985 and spent 11 weeks at No. 1, inspiring a generation of pop culture references, consumer products and fan clubs.

The story of "Back to the Future" is one mired in rejections, challenges and pure luck.

Producer Bob Gale and director Robert Zemeckis wrote the script, which went through numerous drafts and was turned down by dozens of major studios. Five weeks into shooting, the studio had to restart from scratch.

Which means, "Back to the Future" is a classic that almost never made it to the big screen.

Click through the gallery above to learn some "Back to the Future" trivia before your next viewing party.