Marcos and Iván enter Room No.13 through the outer double windows. For a room that has been sealed up and deserted for many years, perhaps decades, a light appears from within to match the lit room next to it; yet, when the boys enter, it's dark. Also, the boys enter through the right window, which looks boarded up from the outside, but from inside it's the left window (where the light seems to shine through) that's boarded up.