New Year, New Challenge!

So, my friends are epic and they make art. And Jill's most recent piece of art is so epic that it has inspired a new challenge! You guys are so good about completing challenges, so I'm sure you'll jump right in! (note the sarcasm)
ANYWAY...

There's the picture. As you can see, it is a fantabulous crossover of things I (and to a certain extent we) love! Your challenge is to write a story about how such a scene would come to be. It can be as long as you want, from whatever perspective(s) you want. Just go with it. Or don't. But I think the results could be hilarious.

Oh, and in case you can't read the text by the London Eye, it says:
-Of course I'll marry you, Michael Aranda!
-Liam and Sara, sitting in a tree!
-Oh PJ!
-Oh, you're so adorable!