Doraemon: Nobita and the Legend of the Sun King

Ledina's spell puts the Mayana queen into eternal sleep. With the queen asleep, Prince Tio acts as temporary ruler while fears of Ledina's rise spread. The stage is set for a clash between ancient magic and the new world that Nobita and friends will unleash.

In modern Japan, Nobita and friends rehearse a Snow White school play. Miscasts and clumsy mishaps disrupt progress and threaten the performance. Doraemon's gadgets complicate things further as the crowd grows restless.

Gian selfishly grabs Doraemon's gadget to perform on an imaginary stadium. The reckless act triggers a crack in time that opens a portal, unstable and unpredictable. The portal unexpectedly links Nobita's world to the ancient kingdom of Mayana.

Popol trashes Nobita's room and hides Nobita's test papers in the forest. Nobita and Doraemon chase the chaos and, through the broken portal, slip into Mayana. The portal's damage blends the two worlds, forcing them to confront a new land immediately.

Nobita is cornered by Tio in the Mayana wilds. They discover that they resemble one another, triggering a tense standoff rather than a killing contest. A struggle sends them into a mud-lake, where Tio realizes Nobita's sincerity and spares him.

Doraemon and the confident Tio step through the portal into Mayana together. Guards mistake Nobita for Tio and seize him on the spot. To avoid capture, Tio proposes a temporary swap of places, a plan Doraemon reluctantly agrees to.

Living as the prince, Nobita faces culture shock and mandatory martial arts training. He surprises the court with his friendly, hopeful approach, in contrast to Tio's arrogance. Kuku, Tio's childhood friend, befriends Nobita and gives him a necklace that signals their bond.

Back in Japan, Tio's volatile temper creates chaos and even beats Gian. Shizuka proclaims she dislikes Nobita in this guise, while Doraemon reveals the switch's truth to the others. The group scrambles to manage the fallout and restore balance.

With the crisis ongoing, Nobita wears the prince's attire to prevent confusion. Gian expresses an interest in Ishumaru's teachings, while Nobita helps Tio win a ball-game match in the Mayana setting. The teamwork shows the reward of friendship transcending appearances.

Kuku offers a string figure to Nobita, but Tio rejects it, hurting Kuku and sending her away in tears. Tio recalls Shizuka's anger when he impersonated Nobita and is driven to apologize. The moment deepens Nobita's influence on Tio's heart.

Ledina's animal-controlling henchman kidnaps Kuku to lure Tio to her palace. Tio sets out on a rescue mission with Doraemon and Nobita's support. They push toward Ledina's palace, facing danger at every turn.

The rescue group reaches Ledina's pyramid temple and is attacked by guardians. A snake pit and a perilous fall of Ishumaru complicate the mission, leaving the team shaken. Nobita uses a spare pocket and a switching handkerchief to substitute for Kuku with a statue, while Ledina burns Doraemon's four-dimensional pocket in rage.

Nobita is captured by Ledina, while the people of Mayana rally to free Tio. Tio volunteers to sacrifice himself to save Nobita, showing his growth in friendship. The sun shines on Kuku's necklace, blinding Ledina long enough for the group to escape.

Ledina's ritual collapses as the temple nears self-destruction and her true elderly form is revealed. A friendly condor, aided by Doraemon's gadgets, helps them escape as Kuku awakens from enchantment with help from Snow White-like rescue. The queen awakens, Tio is named successor, and the portal begins to fade as Nobita says goodbye.

In the end credits, Nobita and his friends rehearse Snow White again, this time with Gian and Shizuka switching roles for a playful finale. The group reflects on their adventures and the power of friendship across worlds. They part ways with memories of Mayana and renewed bonds.