It's evening and like every Saturday you find yourself grocery shopping. Same time as always. The first thing you do as you leave the supermarket is to cover your head with a warm woolen cap. With a brisk pace you head toward your home, not too far from there, to avoid any form of winter flu.

As you walk, you can't help but feel watched. It has been happening for days now but you have always chosen to ignore it. This time it's different: out of the corner of your eye you notice a bright spot behind you. Your paranoia gets the better and, with nonchalance, you turn to look. It's right there that you notice a figure behind the tree.