Dr. Jekyll and Mr. Hyde is a 1988 side-scrolling action video game for the Nintendo Entertainment System loosely based on the 1886 novella Strange Case of Dr Jekyll and Mr Hyde by Robert Louis Stevenson. Gameplay alternates between the characters of Dr. Jekyll and Mr. Hyde based on the player's ability to either avoid or cause damage. Gameplay and premise The story of the game is based on Robert Louis Stevenson's novel, with Dr. Jekyll on the way to his forthcoming wedding to Miss Millicent. The game's ending depends on which character, Jekyll or Hyde, reaches the church first. As Dr. Jekyll walks to the church with his cane in hand, several townspeople, animals, and other obstacles obstruct his path, causing him to become angry. After his stress meter fills up, Dr. Jekyll will transform into Mr. Hyde. The gameplay then moves to a demonic world, where Hyde will fire out a "psycho wave" at enemies. The Psycho Wave is in fact proudly displayed on the game's cover. As Mr. Hyde kills these monsters, his anger abates and eventually he transforms back into Dr. Jekyll. The game features six levels, but the levels differ between the Japanese and North American versions. The Japanese version follows this order: City, Park, Alley, Town, Cemetery, Street. However, the North American version replaces a few levels and follows this order: Town, Cemetery, Town, Park, Cemetery, Street. The North American version also removed certain sprites and segments from the original Japanese version. The player starts out controlling Dr. Jekyll on his way to the church, walking to the right. Contrary to most platformers, Dr. Jekyll cannot kill the majority of his enemies (though he is equipped with a cane,) and as a result, must avoid his enemies rather than confront them directly. As he takes damage from the various enemies and obstacles, his Life Meter decreases and his Anger Meter increases. If his Life Meter is fully depleted, Dr. Jekyll dies and the game is over. If his Anger Meter completely fills, however, he transforms into Mr. Hyde. Day turns to night and monsters appear. At this point, the level is mirrored horizontally and Mr. Hyde walks from right to left with the screen autoscrolling. Mr. Hyde must kill monsters as fast as he can in order to turn back into Dr. Jekyll, with Shepp monsters generally giving the largest refill to his Meter, though