The game's protagonist, Lucia, is an assistant to the scientist Dr. Knavik, alongside her twin sister Cecile. Knavik and co. live in a remote science lab and study ESP and psychic abilities. But Knavik uses alien creatures for his experiments, and one day, they escape and kidnap Cecile! To get her back, Lucia has to use Dr. Knavik's incredible invention, the ESP Booster, to wield psychic powers and defeat the menacing monsters.
The game controls like a typical 2D platforming game, where Lucia moves from left to right while shooting at enemies with her ESP Booster. The Booster has a special meter, above Lucia's health gauge, that displays how much charge it has, which can be replenished using collectibles. There are various different abilities that can be used.
The game was originally published for the MSX under the title Psycho World. When the game was ported to the Master System and Game Gear, the name was changed to Psychic World.