Monk is having a hard time finding a new assistant, and Natalie might be just what he is looking for. But first he has to take her case and solve the mystery of the intruder who seems inordinately interested in her daughter's pet fish.

As sole witness to a murder, Monk is shuffled off to a safe location until he can give a deposition. When a man is killed by lightning while fishing on the lake outside his cabin, however, Monk believes there's more to the man's death than meets the eye.