In order of appearance:
Amu Hinamori and the other four Seiyo Academy Guardians had arrived at the sunny beach. At first, Yaya Yuiki and Amu felt very relaxed in the area until they see the graveyard in shock, which Kuukai Soma mentioned to them that they will be staying at his Grandfather's Temple for a while in that place. While everyone are enjoying their fun time in the sand, Amu stared at her Humpty Lock wondering what she saw that time is the Dumpty Key hanging on Ikuto Tsukiyomi's violin case. But she ignored it for now and join in on the others.
Everyone then stumbled upon a sand sculpturing contest which the winner will win fireworks for the best artistic display. Yaya desperately wanted the winning prize, so Nadeshiko Fujisaki had a good idea to make a prince and princess theme for the sand sculpture, which mistakenly mention that word to cause Tadase Hotori into his wild evil king side again. Everyone started to create the sand sculpture in a group including Tadase still in his Character Change mode. Ran asks Amu what is she making in the sand. She replied that she is making the gateway, which Ran thinks that it looks like a crumbling arc shape. Amu instantly gives up making the gate and says that it is not her character. Miki notices her behavior with an unhappy expression. Suddenly, Kuukai's Grandfather appears with a foul mood telling Kuukai why he and his friends are not there in his place. Kuukai and the others tries to explain a reason to him, which his Grandfather gave everyone a harsh punishment by sitting with their legs in front of the Buddhism Statue inside the temple.
The next day, everyone continues their fun time at the beach including Amu and Kuukai in their Character Change form with Ran and Daichi surfing in the waves. Later, they continue making the sand sculpture before the deadline tomorrow and Amu is still acting the same way as before. Amu asks Miki to character change with her, but she refuses of her selfish act. She explains to Amu that she needs to try her best on her own instead of relying to the Guardian Characters all the time, which causes Amu to ponder of what she meant.
Later in the evening, everyone rushes back to the temple but they were late by Kuukai's Grandfather. He asks them of what they were doing and Daichi answers to him that they were doing the sand sculpturing contest, which causes the grandfather wondering where the voice was coming from. Kuukai covers Daichi's mouth and tells him the truth of why they were late, so the grandfather gave him and the others another punishment by making the girls create dinner while the boys wash the bath. The girls were not very well suited to make dinner on their own, so Su came to help by Character Change with Amu. The boys are surprise to see the delicious food that Amu and Su had made for everyone. Tadase compliments her that perhaps she is suited to become a wife someday, which makes Amu nervously blush in shock.
During the evening, Amu quietly snuck out to finish making her sand sculpture asking Miki to help in plea, which she decidedly will help her but telling her if that is the character that she treated it. Amu pause for a moment then slowly realizes of what Miki had meant when she acted that way when making the sand sculpting. Soon, Amu and the three Guardian Characters are at the graveyard seeing a floating light in the dark. Amu gasp in fright but it was actually Tadase with his flashlight. He asks her if she is okay.
Soon they hold hands together and having some romantic conversation while walking towards the shrine where everybody else is waiting for them. Amu asks Tadase of what he meant of he already had someone he had liked, which for him showing a picture of his dog that passed away last year. Tadase says for the first time that he sees a girl in interest making Amu thinks that it is her, but actually her Character Form Amulet Heart. Amu heard a noise then accidentally hugs Tadase which makes her freak out and apologizing to him. Kuukai and the others are behind the bushes who causes the noise. Kuukai tells Amu that her scream might cause his grandfather to hear them, which it actually did.
Today is the deadline of the sand sculpturing contest as everyone are trying their best to finish their sand-made piece. Amu sees other people giving everything they have in their own willpower. Miki asks her if she wanted to Character Change, but she wants to try it on her own. At the end, Amu and her friends did not win the grand prize, but instead receive a better one as Kuukai's Grandfather had bought a fireworks display set for Kuukai and his friends of their best effort. Everyone is delighted as they play the fireworks throughout the rest of the evening.
- In the anime version, Kuukai's Grandfather lived on a snowy mountain area. In the manga version, he lives on a sunny beach area. Perhaps to give comparison of the themes of summer and winter of the storyline.