Kingdom Hearts (game)
Kingdom Hearts is the first game in the Kingdom Hearts series. Revolving around a fourteen-year old boy named Sora, it details his adventures after his homeworld is destroyed by sinister creatures known as the Heartless, and his attempts to restore his world and reunite with his friends. In the process, he meets many characters from classic Disney films and a handful from the Final Fantasy video game series. The main theme song for the game is "Simple and Clean", performed by Utada Hikaru.
Kingdom Hearts begins with Sora's Dive to the Heart, which foreshadows the events that will soon take place, but soon progresses to Destiny Islands, where Sora lives with his two best friends, Riku and Kairi. The three friends seek to leave the islands to explore new worlds and have prepared a raft for this purpose. One night, the islands are attacked by darkness and shadow creatures. Sora seeks out his friends, finding Riku first; Riku disappears into darkness, curious about what it contains. Soon after, Sora obtains a mysterious weapon, the Keyblade, to defend himself. Using it to fend off the creatures, he heads for a secret cave, where he finds Kairi near a door. She turns to him, saying his name as the door behind her blows open. The ensuing blast of darkness sends Sora and Kairi both out of the cave. The islands are soon destroyed, and Sora is left adrift, Riku and Kairi's whereabouts unknown.
Meanwhile, King Mickey has left his world to deal with the increasing power of darkness and left instructions for mage Donald Duck and knight Goofy to find the "key". Donald and Goofy use a Gummi Ship to travel to Traverse Town, where it happens Sora has also drifted to. Sora encounters the creatures again in the town, and eventually meets Leon, a mysterious swordsman who explains they are Heartless, creatures that consume hearts, and that the Keyblade is the only weapon capable of defeating them. The king of Leon's home world, a man named Ansem, is said to have studied the Heartless. Donald and Goofy are approached by Leon's ally Aerith, who also tells them what they may be looking for. Soon after, Sora meets Donald and Goofy rather hastily, and the three work together to take down a large Heartless. From there, they decide to travel together: Donald and Goofy to find Mickey, and Sora to find Kairi and Riku.
The three travel to various worlds based on Disney films, finding that the Keyblade also locks "Keyholes", passages that the Heartless use to take the heart of the world. A group of villains, led by Maleficent, seek out the seven Princesses of Heart to unlock the Keyhole that leads to Kingdom Hearts, a repository of knowledge and power and the source of all hearts. This group now includes Riku, who is swayed by Maleficent's promises that she will help find Kairi. At the same time, Maleficent sows distrust in Riku, telling him that Sora has abandoned him and Kairi for new friends and the Keyblade. An increasingly antagonistic Riku manages to find Kairi's body, but her heart is missing.
Sora and his friends eventually arrive at Hollow Bastion, the home world of Ansem and the headquarters of Maleficent. Riku takes the Keyblade from Sora, claiming that he was fated to have it all along and Sora was simply the "delivery boy". Donald and Goofy, taking their order to follow the "key" seriously, reluctantly leave with Riku. Sora calls on his courage and enters the Bastion anyway, then challenges Riku again, stating that his heart derives strength from his friends. His friends return to him, as does the Keyblade. Shamed, Riku flees and meets a cloaked man who goads him to give into the darkness.
Sora, Donald, and Goofy, meanwhile, engage and destroy Maleficent. They soon after meet a strangely-behaving Riku with a new Keyblade that unlocks hearts. He leads them to Kairi's living but unfeeling body; Riku then reveals himself as completely possessed by Ansem. The newly reformed Ansem explains that Kairi is the last Princess of Heart, and that her missing heart has been trapped within Sora's body since the destruction of Destiny Islands. Spurred to action, Sora defeats Ansem; however, he cannot seal Hollow Bastion's keyhole because Kairi's heart is still in his body, thus the keyhole remains incomplete. Sora uses Ansem's Keyblade to unlock his heart, releasing both his and Kairi's heart, but turning him into a Heartless. Kairi's heart returns to her body, in turn completing the final Keyhole; she then returns Sora to human form by the strength of her heart. The group resolves to follow and end Ansem's plan.
Ansem retreats to the End of the World, the combined fragments of worlds taken by the Heartless. Upon being found and finally beaten, he explains his belief that darkness is the heart's true essence, and he seeks Kingdom Hearts, the source of all hearts, and therefore the ultimate source of darkness. However, upon opening the door to Kingdom Hearts, it reveals Light, killing Ansem. Beyond the door are Mickey and Riku, back in control of his own body. They help Sora and the others close the door, as there are many Heartless beyond it, but Riku and Mickey must remain inside to help seal it. Mickey and Sora then use their Keyblades to lock the door. The destroyed worlds reconstruct themselves; Kairi is pulled back to the Destiny Islands, but Sora promises before separating they will all reunite some day. Sora, Donald, and Goofy resolve to find Riku and Mickey, though they are unsure of where to start. Luckily, Pluto appears, clutching a letter from Mickey in his mouth; he runs off with Sora, Donald, and Goofy in tow, ready for a new set of adventures. The silent narrator from the beginning of the game states in the final scene that Sora's destiny is to open the door to light.
 Final Fantasy Characters
Square Enix, the makers of the game, inserted several characters from their own popular Final Fantasy game series into the storyline.
Squall Leonheart (Leon)
 Temporary Party Members
Temporary Party Members are world-specific characters that join Sora's party to help him during the time he spends in that said world, and as such, will only be present in the world they come from. They are characters that Sora meets and befriends during his search for Riku and Kairi. Each character can become a party member, by switching him/her with Goofy or Donald.
Tarzan (from "Tarzan")
Aladdin (from "Aladdin")
Ariel (from "The Little Mermaid")
Peter Pan (from "Peter Pan")
Beast (from "Beauty and the Beast")
Throughout his travels, Sora finds summon gems, which he can bring to the Fairy Godmother, and be granted a summon from the gem. In reality, the gem is the heart of the summon, created when the heart of a world is devoured by the Heartless, but with the heart of one of the residents being too strong to be consumed. Summons take the place of the two AI members of the player's party, and as such, both AI must be conscious before the player can use a summon. Pride Lands, The Land of Dragons and all worlds were destroyed by the Heartless, except Agrabah and Neverland.
Simba (from "The Lion King")
Tinker Bell (from "Peter Pan")
Genie (from "Aladdin")
Bambi (from "Bambi")
Dumbo (from "Dumbo")
Mushu (from "Mulan")
Most of the villains in Kingdom Hearts are taken from the various Disney films that are featured in the game. The most notable Disney villain in the game, however, is Maleficent (from Sleeping Beauty), and appears at first, to be the main villain of the game. However, it happens that an original character, Ansem, Seeker of Darkness, is the main antagonist of the game. Both of these characters are major bosses with Ansem serving as the final boss.
These are the "main" antagonists of Kingdom Hearts, with the majority often seen conspiring together as a group in the ruins of Hollow Bastion.
The Heartless are living beings, whose hearts were corrupted by darkness, and they play the roles of the "common enemies" Sora and party must defeat. They exist for no other purpose than to consume hearts, be it the hearts of other living beings or even that of entire worlds. If someone loses their heart to a heartless, they themselves become one.
In general, there are two types of heartless, commonly referred to as Pureblood Heartless, who are created "naturally", and Emblem Heartless, who are artificially created. The Emblem Heartless received their name because upon creation, they were all branded with an emblem, in order to distinguish them from the Purebloods.
 Other releases
 Kingdom Hearts Final Mix
Kingdom Hearts Final Mix is an extended version of Kingdom Hearts. Released only in Japan, it uses most of the revisions made for the North American and European releases. It features other additions to the original game: a Final Fantasy X-2 trailer (named "Special Movie") on the main menu, three new Difficulty Levels: Beginner, Standard, and Proud mode, new types of Heartless and palette swaps for most returning Heartless, new Keychains and items, and a new secret boss that appears in Hollow Bastion, known only as "Unknown". It also features an expansion of the secret movie from the first game, Another Side, Another Story [deep dive], foreshadowing more of Kingdom Hearts II.
 HD Remaster
Kingdom Hearts Final Mix was re-released in high definition as part of Kingdom Hearts HD 1.5 ReMIX.