This is it! The holidays have started, the turkey is defrosting and the presents are all wrapped ... all you have to do now is relax and be kind to one another. So the very last door of our advent calendar is devoted to love. The Plus team wish you a very merry Christmas and a happy new year!

Oh, Christmas is so magical! But of course magic often boils down to being surprised. Find out how mathemagicians trade off the fact that you can usually predict precisely the outcome of doing something in mathematics, but only if you know the secret beforehand. Here's for some maths and magic!

Mathematicians are often good musicians. To prove this, here are some impressive compositions. Enjoy!

It's time to get out those party invitations! Trouble is, your sister doesn't get on with your boyfriend, your boyfriend doesn't like your best mate, and your best mate's just broken up with your cousin. Who do you invite?

Oh, those beautiful snowflakes! They've put us in the mood for fractals, so let's celebrate some favourite shapes.

For those of you whose holiday has already started, here are a couple of christmassy puzzles to cuddle up on the sofa with.

As the odds for a white christmas in the UK shorten and we rug up for another snowy weekend, let's look behind door #17 for the latest forecast...

Stave off the holiday boredom with a game or two behind door #16...

Need help with your Christmas shopping? Look behind door number 14...

Got your popcorn? Picked a good seat? Are you sitting comfortably? Then let the credits roll... Mathematics of the big screen is behind door #12...