Derren Brown gives an undertaker some pictures and asks him to deal them into two piles - one with pictures he likes and one with those he doesn't. When they turn the pictures around, it turns out he had disliked the pictures of dead people and liked the pictures of those who are alive. You can see the trick here.
This is actually a version of a classic card trick called Out of this world. It is the same thing, only using pictures instead of cards. The only difference is that he replaced the bottom parts of both piles when the undertaker was distracted. That way, one whole pile has alive written on it and the whole other pile has dead. For the explanation of the card trick, click here.