The famous detective Sir Charles Foxworth is taking a holiday on the Mississippi with his servant Regis on the Delta Princess . He's just taking a stroll around the upper deck of the ship when he discovers an open cabin door. Behind it: a dead man. As it turns out, the body of Raleigh Cartwright III. Sir Charles has three days to find the murderer, because then, the ship will reach New Orleans, giving the culprit a safe chance to escape.
The gameplay involves using the joystick controls to move into different directions and pressing buttons to access menus with commands for the current situation. The player can walk around, inspect items, or examine evidence. Meeting characters who are also suspects allows the player to gather information by taking notes on what they say. Sharing these notes with other passengers and crew members becomes more useful once the body has been found.
The goal is to collect as many notes and evidence as possible to solve the mystery. Once a solution is thought of, the player must accuse one of the suspects by pointing to them using the joystick and pressing the button. The outcome depends on the amount of evidence collected, and there are four possible endings with many variations.
Murder on the Mississippi for the Commodore 64 was released in 1970 . The game requires the player to solve a murder mystery before the ship reaches New Orleans. With its unique gameplay mechanics and multiple endings, it's a challenging and engaging experience. 
