Kingdom Hearts II begins one day after Kingdom Hearts 358/2 Days or one year after Kingdom Hearts and Kingdom Hearts: Chain of Memories.

Sora, Donald, and Goofy have been asleep in suspended animation for the past year to regain their lost memories. Meanwhile, Roxas, the Nobody of Sora is trapped in a virtual simulation of Twilight Town created by DiZ so that he may merge with his original self to restore Sora's power done as part of DiZ's revenge on Organization XIII. DiZ's plans are threatened when Organization XIII's Nobodies, led by Axel, Roxas's former friend in the Organization, infiltrate the virtual town, but Roxas finally merges with Sora. Sora, Donald, and Goofy wake up in the real Twilight Town and meet King Mickey and Yen Sid, who send them on another journey.

Their goal is to find Riku and stop the plans of Organization XIII, who control the Nobodies - the body left over when a heart is turned into a Heartless. Sora also receives a new set of clothes that allow him to fuse with party members to gain special abilities. From there on their jurney begins on traveling to the many worlds!

In September 2006, Square Enix announced they would develop Kingdom Hearts II Final Mix, featuring new scenes and gameplay elements.

Kingdom Hearts II was re-released in Japan on March 29, 2007 as a 2-disc set titled Kingdom Hearts II Final Mix+. The first disc contains Kingdom Hearts II Final Mix, with a new secret movie and additional battles and items. The second disc contains Kingdom Hearts Re:Chain of Memories, a 3D PS2 version remake of Kingdom Hearts: Chain of Memories with extra scenes and voice acting. The battle system maintains the card gameplay, with the addition of Reaction Commands from Kingdom Hearts II. The two games also serves as a canonical update to the series. The book, Kingdom Hearts -Another Report-, was included along with the game for those who reserved a copy.

MANGA

A manga series started its serialization in the June 2006 issue (released on May 12) of the magazine Monthly Shonen Gangan, published by Square Enix. The artist is Shiro Amano, who also did the Kingdom Hearts and Kingdom Hearts: Chain of Memories manga series.

The first volume was released in Japan in December 2006. Tokyopop licensed the manga and released volume one in North America on July 3, 2007. The game has also been novelized by Tomoco Kanemaki and illustrated by Shiro Amano. The first volume, titled "Roxas - Seven Days", was released on April 22, 2006 and covers Roxas' story to when Sora wakes up and leaves Twilight Town. The novel depicts extra scenes that were added in the Final Mix version, such as interaction between Organization XIII members and between Axel, Naminé and Riku. The second book, "The Destruction of Hollow Bastion," was released on July 16, 2006. The third book, "Tears of Nobody," revolving around Roxas' past, was released on September 29, 2006, and the fourth, "Anthem-Meet Again/Axel Last Stand," came out in February 2007.