When an overenthusiastic neighborhood watch group asks Magnum and Higgins to investigate a shady character living on their block, they are shocked to find that they may have inadvertently stumbled upon a serial killer on the loose. Also, Jin's new money laundering business leads him to want to help a new friend.

When Higgins is abducted, Magnum discovers it's retaliation related to one of his first cases on the Island, and he, Rick and TC must break out an ex-client from prison in order to save her.