On Halloween, Magnum and Jin (guest star Bobby Lee) search for a skip-tracer at a Halloween bash, just as Katsumoto tracks an escaped killer who is headed to that same party. Also, Higgins and Rick must spend the night at an allegedly haunted house in order to debunk the notion, and TC and Kumu protect a sacred Hawaiian burial ground.

While Magnum helps out his friend Russell Harlan and temporarily works as the head of a hotel's security, he investigates the death of a guest who was thrown from her room's balcony while working on a secret investigation of her own. Also, Icepick is released from jail and is trying to keep a secret from Rick.