One player begins as a 'spy' who has a mystery three-letter word which the other player (s) (or detective (s)), must discover. To do so, the detectives play cards from their h&, each of which contains a different three letter word. As the card is played, the spy must reveal how many letters each new word has in common with the mystery word. As more cards are turned, the detectives must use logical deduction to work out the mystery word. The game comes with three different levels of difficulty. A brilliantly thought out game!