During an after-school shopping trip, Sakura Kinomoto decides to participate in the Tomoeda Shopping District's year-end lottery, with the grand prize being a round trip to Hong Kong. Surprisingly, she draws the winning ball. Alongside her best friend Tomoyo Daidouji, her older brother Touya, her crush Yukito Tsukishiro, and Keroberos, Sakura heads off to Hong Kong. However, vacation for the Cardcaptor will get cut short. Little does Sakura know, the trip may be connected to her recent, prophetic dreams featuring a mysterious woman and Clow Reed himself, creator of the Clow Cards.

The future of the universe rests on one young man, Kamui Shiro, who must destroy either the Dragons of Earth or the Dragons of Heaven - two opposing armies. He alone must decide whether humanity should be destroyed to create a purified universe, or whether it should be protected to preserve civilization. Two oracles, the sisters Hinoto and Kanoe foresee the coming of the Dragons and predict opposite outcomes. Each sister gathers strength and ammunition to insure her own vision for the future. However, neither sister realizes that there is one man who has an even greater power than the Dragons, and that ultimately he will determine the fate of the earth. Which sister will prevail and how does Kamui fit into their struggle? The answer to this question will forever affect humanity. (Source: Manga Entertainment)

For this year's Nadeshiko Festival, Sakura Kinomoto's elementary school class is presenting a play. She will portray a princess who struggles to respond to the love confession of the neighboring country's prince. Sakura empathizes with her character all too well, since she herself still owes an answer to the boy who confessed his love for her four months ago. When cousins Shaoran and Meiling Li return from Hong Kong to pay a surprise visit to their friends in Japan, Sakura receives further encouragement to finally declare her feelings. However, she is repeatedly distracted by a presence reminiscent of a Clow Card as well as unexplained disappearances around town. Eventually, Sakura learns of another of Clow Reed's creations—the "Nothing"—which was formerly sealed away beneath the magician's old house. It has power equal to all 52 cards Sakura possesses, and furthermore, it wants to take those cards away from her! Objects, space, and people disappear from Tomoeda with each card that is stolen. Sakura sets out to capture the Nothing so everything will return to normal, but what must she sacrifice in the process?