Andy, Brian, Celine, and Drake were captivated by a very bad person and were positioned as what can be seen in the picture below. All of them face a wall. Each of them was given a hat. No one of the four knows the colour of the hat that is worn by themselves, but they know that there are 2 red and 2 blue coloured hats.

The bad person told them that one of them have to name the colour of the hat him/herself wore. There’s only one chance. If the answer is wrong, all of them will be killed.