Dr. Jekyll seeks to hide his dual nature without losing his sanity, while Mr. Hyde, his alter ego, seeks to dominate him and make him fall into darkness.

One of the players plays Dr Jekyll, the other will be Mr Hyde. The game is played in three rounds.

At the end of each round, Dr. Jekyll's personality sags under the onslaught of Mr. Hyde. Mr. Hyde wins if he manages to get the marker to the other end of the track (at the left end).

If he hasn't managed to do it in three rounds, Dr. Jekyll wins, freeing himself from his opponent's evil influence.