NiGHTS: Journey of Dreams is a sequel to the 1996 Saturn title NiGHTS into Dreams... . Like the original game, Journey of Dreams tells the story of the dream world of Nightopia which is being threatened by nightmare creatures called Nightmaren. The game introduces two children, William and Helen, and in their dreams the game takes place. The player controls the children and also Nights, a Nightmaren that turned against his creator in the previous game, and must protect the children's dreams from the Nightmaren.
The gameplay of NiGHTS: Journey of Dreams begins with choosing a dreamer to play (William or Helen) and one of the seven worlds. The player can initially roam the world as the dreamer until he merges with Nights. Once Nights is controlled, the game turns to the traditional gameplay of gliding and spiraling through loops and collecting orbs and Dreamdrops.
During the game, the player can obtain Persona Masks used to transform Nights into various animals and vehicles like a dragon, a dolphin, a rocket and a boat. These masks assist the player in reaching areas not accessible otherwise.
The game also features a sandbox environment called My Dream, where players can raise Nightmaren and other creatures of Nightopia using the Forecast Channel on the Wii. The game allows for four different controls schemes: the Wii Remote, the Wii Remote with the Nunchuk, the GameCube controller and the Classic Controller.
Players can keep track of their global ranking in an online scoreboard as they play, and the game informs them of their rank when playing.