This game takes place after the events in Ape Escape, where Kakeru (Spike in the U.S. version, Spike in the British version of the original Ape Escape) stopped Specter from taking over the world. It is a few years later, and The Professor left for a vacation leaving his granddaughter, Natsumi (Natalie), and Kakeru's cousin, Hikaru (Jimmy) to watch over the laboratory. Professor has left them with one task: deliver a load of monkey pants to the monkeys in Monkey Park. Hikaru accidentally sends not only the monkey pants, but The Peak Point Helmets as well. Specter gets a hold of one, and yet again makes an army of monkeys bent on ruling the world. Jimmy aims to capture all the monkeys and stops Specter.
Gadgets are Hikaru's main forms of offense and defense.
Stun Club - This is Hikaru's basic weapon. It can defeat most enemies in a few hits and can break things and answer help telephones.
Monkey Net - This is Hikaru's most important tool. It catches monkeys.
Monkey Radar - This device helps Hikaru locate monkeys and find out their statistics.
Super Hoop/Dash Hoop - A hula hoop that allows for Hikaru to travel very fast and damage enemies.
Slingback Shooter/Catapult - A slingshot that fires normal, explosive, and guided pellets.
RC Car - This car helps Hikaru attack enemies, collect items, and reach switches from afar. There are 5 different chassis.
Sky Flyer - A helicopter - like device that lets you glide for a short while.
Bananarang - This boomerang emits a banana - like scent that attracts monkeys. (note this gadget will not work on monkey white,pink and red.)
Water Cannon - A water gun that can put out flames and distract monkeys.
Electro Magnet - A magnet that can move or attract metal items and remove enemy armor.
Magic Punch/Power Punch - This is the ultimate weapon that defeats all enemies in one hit, except bosses. It can also destroy objects that no other gadget can destroy. You only get it after defeating Specter.
Minigames
Like in the previous game, Ape Escape 2 features minigames, this time to get them you pay for them via a vending machine in the hub when you've got up to a certain stage in the game. The minigames are:
Dance Monkey Dance: A dancing minigame similar to the Dance Dance Revolution Series where the player competes against other monkeys in a dancing contest. Alternatively, the player can dance alone and is reviewed on his or her dancing by judges.
Monkey Soccer: A minigame similar to the FIFA Series where the player plays against other teams in a soccer game. You can use monkeys captured in the game to replace the ones you are given by default.
Monkey Climber: In this minigame the player has to make the monkey climb up the vines by repeatedly tapping the analog stick buttons.