Lesson 4: Never go Christmas shopping.

Where we learnt it: Enemy Of The State, Serendipity

Why: Because if you’re Will Smith you’ll accidentally discover incriminating evidence that’ll cause you to be hunted down by rogue government agents, and if you’re John Cusack you’ll find out that your one true love is a woman who starred in Van Helsing. Either way, it’s probably best to get your gifts on the internet this year.

Lesson 5: Never travel at Christmas.

Where we learnt it: Cast Away

Why: If you get on a plane this Christmas, you will crash on a desert island, and after a couple of years you’ll be so lonely and skinny that you’ll start talking to a volley ball. Seriously, Cast Away thinks that winter getaway to LA is a really bad idea.

Lesson 6: Losing weight makes you have an affair.

Where we learnt it: Just Friends

Why: According to Just Friends, one minute you’re a likeable fatty, the next you’re the sort of person who goes back to his home town for Christmas in a Porsche to try and woo his high school crush, even though he’s in a relationship. What a bastard.

So, if you’re in a loving relationship, do what Just Friends suggests and eat as much as humanly possible. It’s the only way you’ll stay together.

Lesson 7: Father Christmas is a child-snatcher

Where we learnt it: Elf

Why: In the opening moments of Elf, Santa is in an orphanage delivering presents. A kid crawls into his sack and Mr Claus accidentally takes him home. Fair enough, St. Nick doesn’t notice until he gets back to the North Pole.

But when he does, he decides to keep the kid. That makes Santa a child snatcher in our eyes, and you should probably fill your chimney with razor blades this year, just in case the fat man decides to take your first born.

Lesson 8: Be as mean as possible, and you’ll get to hang out with ghosts.

Where we learnt it: Scrooge, Scrooged

Why: We spent most of our childhoods hunting for ghosts. If only we’d realised that all we had to do is kick our best friends in the shin and not one but three ghosts would want to come and hang out with us. Not only that, but they’d be/time travelling ghosts. If we’d have seen Scrooge a few years earlier, there would have been a lot of bruised legs in our vicinity, that’s for sure.