Okay, here's a nice little problem to apply your mind to as you begin to unwind from the festive frivolities of yesterday.
Imagine that you're the father of two teenage daughters. While they're out shopping, a friend of yours phones you and suggests you should look up a video that has been posted on a popular video sharing website. He says he could be mistaken but it appears to feature your daughters. You take a look, and there's no mistake. You even know when it was taken because of the clothes they're wearing and the fact they were at a party in that part of London just a few days ago. That leaves you with a couple of hours to work out what you're going to do when they get back from the shops.
Here is the video...
And your response will be...