"What happened here? Is anyone bleeding? Anyone else got hurt?" one of the security guards said, seemingly puzzled.

Startled by the guard's question, Lisa followed the guard's gaze and saw the bloodstain on the escalator steps. The blood stains were barely noticeable on the dark gray escalator, so Lisa had missed it earlier.

That bloodstain! It must be Terry! Terry had fallen on this spot earlier. He was bleeding!

Lisa felt something pressing on her chest, making her breathless. Terry was