Three guests at the plushest hotel in Los Angeles die in their beds under mysterious circumstances. The hotel manager breathes a sigh of relief because he believes in the old superstition that bad things happen in a cycle of three. LAPD Detective Ed Browning and his partner aren't buying the manager's tale. They start investigating and soon hear the story the sister of the dead girl seeing her sister's ghost, talking to her, and learning her death was not by natural causes. More suspicious than ever, Browning and partner then are suddenly told to back off by their captain. This makes them even more doubtful that two old people and one young died of natural causes in the same hotel. Since they can't officially investigate, they turn to their friend Maisy Malone for help. Maisy rounds up a cadre of fellow amateur sleuths and sends them out to do the leg work Browning and his partner can't do. Maisy and company hit the streets and highways to dig up evidence, and in four days they meet at the same hotel with their witnesses and suspects.