In this mystery, players control Inspector Snide of Scotland Yard who has been sent to MacFungus Mansion to investigate the death of its owner, Angus MacFungus. The aim of the game is to gather information and clues from around the house, solve the case, and implicate the murderer.
When Snide is in the vicinity of an item of interest, the border will flash. Pressing Fire on the joystick brings up a menu of six commands. Some of these commands allow you to examine, manipulate, and utilize objects; or check the time. Players can only carry six objects at a time, unless they already have something to carry them in.
People roam around the mansion, and players can interrogate them by bringing up the menu and choosing the Question icon. The characters will stop what they are doing, and the player must face them in order to interrogate them. Players can question them about MacFungus, objects, or other characters.
Every once in a while, a murder takes place involving one of the characters. Players have to collect the necessary evidence and accuse the murderer before time runs out.