As the group walks up the stairs to the third floor, I hear a sound from up the stairwell, a couple of floors above us. I suspect I wouldn't have been able to hear anything if the echoes hadn't travelled all the way from what I assume is one of the top floors. As the sound reaches me, I hear the coughs of an old man. What if someone who hasn't been informed about the fog is up there with their window open, trying to find out what's going on only to be met with the horror of the toxic air? I'm about to stop my friends and tell them about my suspicion when I spot Brad and Ash limping in front of me. They should rest—I thought—and if I tell them about the sound I heard then it would be impossible to get them to agree to let me check it out on my own.