One day, while listening to Laura and Kana plan an evening barbecue, Hamtaro becomes enchanted by what the girls are eating--a sparkling candy called “Diamonds of Sugar”. Puzzled, Hamtaro goes to the Ham-Ham Clubhouse to ask his friends if they’ve heard of these "diamond things". After many theories from the hamsters, Boss insists the candies come from the sky and are best seen at night.

Laura's parents take her on her first trip to the beach; but when they tell her that the water can be dangerous for hamsters, she decides not to take Hamtaro. However, Hamtaro and the Ham-Hams have other ideas! They want to see the ocean, so they make a plan to go to the beach too, after agreeing that if they stick together, they can look out for one another.

It's a summer festival! The Ham-Hams learn from Maxwell that on the night of the festival, flowers (fireworks) will appear in the sky. Pashmina separates from the Ham-Hams to find the flowers.

Hamtaro goes with Laura and her family to visit her grandmother in the country. The Ham-Hams are excited for Hamtaro, because Grandmother's house is surrounded by sunflower fields.