Tie the murder-mystery game to the cruise ship by giving players characters from the old television show "The Love Boat." No matter the size of your murder-mystery group, you can have guests be Captain Stubing, Dr. Bricker, bartender Washington, purser Smith and, of course, cruise director Julie. Larger groups can include lesser-known cast members or add parts such as cruise entertainers and guests. Before players arrive on the ship, distribute cast biographies and some details about each character so that even if guests haven't seen the television show, they can get into the game.
Cruise ships are known as floating cities, with everything from basketball courts and climbing walls to triple-tiered theaters and dance halls among the ship's levels. Ships also offer shops, bars, salons and spa, a gym and restaurants; use them all for the murder mystery as a way of getting guests familiar with the ship and adding excitement to the game. Drop clues about different areas of the ship (such as, "I have chips, but you can't eat them" for the casino, or, "On this bridge, nothing drives under me" for the captain's navigation area), then lead players on a wild goose chase to pick up clues about the murder.
You can't have a murder mystery without a murder, so arrange for the murder and murder weapon to be cruise-ship-related. For example, the murdered person could be found by the group squashed beneath a replica of the giant, wooden captain's steering wheel or slumped over, poisoned, in one of the ship's bars. Other ideas include the murder weapon being thick ropes used to anchor the ship in port (strangling/hanging), choking on a casino chip or poker card--or, to avoid a scene, game organizers can report that the victim fell or was pushed overboard off a balcony or the rear of the ship.
