If the first part in our list of 20 things you didn't want to know about Christmas movies didn't leave you feeling Grinchy enough, the second instalment will definitely make your heart feel at least three sizes too small.

11. How the Grinch Stole Swing-mas

The Whos in Ron Howard's live-action version of 'The Grinch' aren't as wholesome as the ones in the 1966 cartoon. In one flashback sequence at a Who holiday party, guests are seen putting their keys in a bowl — meaning they're going to hook up with whomever draws their keyring from the dish later on.

12. Bat-Brothel

The Whos aren't the only critters that get frisky around the holidays. The caretakers of the penguin army featured in 'Batman Returns' wound up leaving with more birds than they arrived with after some laid eggs during the shoot. So while you're watching the film, keep in mind that at any given moment, there's problem a penguin having sex behind the scenes.

13. The Santa Clause Hotline

Disney's family-friendly film 'The Santa Clause' was an unexpected Christmas present for the adult entertainment industry thanks to Tim Allen's off-color joke.

At one point in the movie, Allen jokes that another character's phone number is 1-800-SPANK-ME. Which happened to be the number for a real sex line. But Disney didn't realize that until irate parents called them up to complain after their kids dialled the number.

The line has since been removed from re-releases of the film.

14. A Literally Lethal Weapon

Mel Gibson decided to raise the stakes in one scene from the yuletide action flick 'Lethal Weapon' by putting a real bullet in the gun that his character stuffs into his mouth while contemplating suicide. So we were one flinch away from 'Lethal Weapon' turning into a Christmas snuff film.

15. Loose Lips Almost Sunk 'Scrooged'

Production of the dark comedy 'Scrooged' had to shut down for a few days while Bill Murray's face healed after the sadistic Ghost of Christmas Present (Carol Kane) accidentally tore his lip while while grabbing his mouth in one scene.

16. The Nightmare Before Multiculturalism

The 7 holiday doors in 'A Nightmare Before Christmas' represent Halloween, Christmas, Valentine's Day, St. Patrick's Day, Easter, Independence Day and Thanksgiving. That means the fictional world doesn't recognize non-Christian celebrations, so there is no Ramadan Town or Hanukkah Town (where people would presumably sing Adam Sandler songs year-round).

17. Christmas Evacuation

During a shopping trip in 'National Lampoon's Christmas Vacation,' Cousin Eddie asks Clark if he worked for the company that "killed all those people in India" — a reference to the Bhopal Disaster, in which gas leaking from a pesticide manufacturer killed thousands of people in 1984.

18. Love Hurts

The lake that Colin Firth and Lúcia Moniz jump into in 'Love Actually' was actually a shallow, mosquito-infested pool. Both actors suffered many bites during the shoot, and Firth had to seek medical attention for one bite that swelled to the size of an avocado.  

19. Die Often

Medical professionals say John McClane (Bruce Willis) would've died at least 3 times from injuries sustained while fighting terrorists that crash his wife's Christmas party in 'Die Hard.'

20. Die Hard 2: Die Softer

Don't get fooled by the 'Die Hard' sequel's subtitle 'Die Harder.' John McClane would likely survived all of the injuries sustained in the movie, so the follow-up is actually much softer than its predecessor.