A 12-year-old boy is found dead at the bottom of the family pool after going for a midnight swim. While Dr. G can easily establish that the boy drowned, finding out what caused the drowning may be more difficult. The boy has a history of depression and drug use, making suicide or accidental overdose possibilities. Just when Dr. G thinks she has found the answer, a new piece of evidence surfaces that puts everything into perspective.A 31-year-old man lying motionless on the railroad tracks is hit by a train. Did the man commit suicide, was he murdered and placed on the tracks, or did he pass out on the tracks due to alcohol abuse or a natural medical emergency? It's up to Dr. G to find out.