Five million people travel through the São Paulo subway every day. So do an infinite number of tormented souls.
Under the eyes of her children, the mother collapses on the tracks of the Trianon-Masp station. What would have been a suspected suicide takes on unusual twists when a paranormal investigator identifies a confused, frightened witness with memory problems. She assures him that something - a "shadow" - had pushed the woman to death.
