We all know Harry Potter and Lord of the Rings were based on epic novels, right? But what about Die Hard? Mrs Doubtfire? Here’s our rundown of some films you didn’t know started out life as books.

Die Hard (1988)

Die Hard?! Dafuq?! Yes, you heard us correctly. The oh-so-totally-80s action flick that propelled Bruce Willis to A-list fame was actually based on a humble paperback.

Roderick Thorp’s novel Nothing Lasts Forever was first published back in 1979 – the book and the film follow pretty much the exact same plotline (‘cept the book’s got fewer ripped vests and ventilation ducts) so there’s not much to catch you up on. Yipee-ki-yay mother… er, booker?

Shrek (2001)

Who knew that the loveable double-act Shrek and Donkey actually came from a cutesy kids’ picture book?! The animated movie, which grossed more than £400million at the worldwide box office, was loosely based upon Shrek! written by American cartoonist William Steig.

The film stole our hearts, largely thanks to its fabulous casting, constant innuendo and numerous fart jokes. God knows what number we’re up to now, but the first two are definitely worth a (re)watch – especially ‘cause you’ll now actually get the jokes that went over your head as a kid. Such as, ahem, ‘Lord Farquaad’ totally being called ‘Lord F*ckwad’. Ever noticed? LOLS.

Pirates of the Caribbean (2003)

Did you know that Johnny Depp’s swashbucklin’ saga was inspired by a ride at Disneyworld? 10 points if you already did. The ride itself was actually based on the 1950 movie Treasure Island, which in turn was based on the book by Robert Louis Stevenson wrote way back in 1883.

Now this is where it gets complicated. That book was based on a map, which Stevenson once drew with his stepson. But, the map in the book wasn’t the original map – that had gotten lost and had to be drawn again. SO, the film Pirates of the Caribbean is actually based on a ride, based on a film, based on a book, based on a map, based on a map that the author once drew for a laugh.

Wow, that’s some serious storyline-inspo inception going on right there. Confused much?

Mrs. Doubtfire (1993)

Ah, Robin William’s unforgettable, iconic portrayal of the barmy babysitter will always remain unchanged in our hearts (SOB). But did you know Mrs. D. was actually based on a book about an Edinburgh-based shopkeeper?

Anne Fine’s acclaimed novel Madame Doubtfire was published in 1987, inspired by a batty ol’ lady who owned a bric-a-brac store round the corner. Apparently, the author claims that there’s no ‘real’ connection between the book and the film, yet both feature a flamboyant, cross-dressing granny called Doubtfire. Coincidence? Doubtful.

Mean Girls (2004)

It must have been divine intervention when Tina Fey picked up her copy of Queen Bees & Wannabes: Helping Your Daughter Survive Cliques, Gossip, Boyfriends, and the New Realities of Girl World. Fortunately, the movie she made after reading it had a much snappier title.

The book itself is actually non-fiction (if only Cady Heron had a copy…) and explores the terrifying world of American high schools. It also includes advice on how girls can survive “the jungle” and what to do about any Regina George-types they might encounter along the way. SO fetch.

There’s kind of nothing more annoying than when you watch a cool film and somebody goes in that patronising voice “Ohhhh, you’ve got to read the book.” But now, you can get one over on said annoying someone, with these fabulous book-to-film adaptations that you never even knew about!

Speaking of books, we’ve got one too good for you to miss out on. Bag yourself a Revolution Card for just £3, and we’ll bestow upon you the magical, mythical Book of Legend. It’s packed with £100 worth of insanely great vouchers, so you can round up your pals, divvy ‘em all out and say “Four for you Glen Coco, you GO Glen Coco”…

Or, you can just keep ‘em all to yourself! Yay!