You grab your favorite snack (a bag of jumbo puff marshmallows) and turn on the TV to watch the movie Alien. Just when it's about to get to your favorite scene (the chestburster), your power goes out. With no idea what's going on, and your heart rate already slightly elevated, you begin to panic. You begin to smell a faint odor that you don't recognize.
This time, it's not the dog.
A viscous, dark green liquid starts crawling out from beneath the door. You quickly tuck your knees up and crouch on your sofa. The green fluid starts to glow, an unerving regular beat - almost like - no, it couldn't be - you realise it is your heartbeat and start to panic. Why is it the same?