5th-grader Laura Haruna owns a hamster, and his name is Hamtaro. After moving into a new town, Hamtaro finds that he's in the company of lots of different hamsters, making up a group of hamster friends that go on crazy adventures through the city. Before they save Laura and other humans from nasty predicaments, however, they have to learn how to save themselves.
 
(Source: Anime News Network)

The children's manga series that sparked an international phenomenon. 
The three books - A Home for Hamtaro and Other Stories, Hamtaro Gets Lost and Other Stories, and Jealous Hamtaro and Other Stories - each follow the adventures of a different Hamtaro, but they all share the same sweet, innocent feel.

Laura tells Hamtaro where he came from yet Laura thinks it is not true, just in time for his birthday, Hamtaro sets out with Boss and Oxnard to visit his mother to see if what Laura said is true, while the other Ham-Hams set up a surprise birthday party for him. 
(Source: Wikipedia)

It's Laura's birthday, and Laura isn't paying much attention to him. Hamtaro then went with the ham-hams to ham ham land. Hamtaro is searching for the magic sunflower seed, but, he will have to battle Maou-hamu for it.

Lately, Hamtaro has been having a strange dream. In the dream, a beautiful princess hamster tearfully asks for help. Hamtaro can’t forget about her, even when he’s awake. One winter day, Laura talks to Hamtaro. She tells him that everyone in the family is going home to her father’s hometown. When Hamtaro tells his friends about it, Maxwell pulls out a Ham-Ham source book. It’s a book on old hamster history. 
According to the book, there is a “homeland” for hamsters called “Hamja Kingdom”. When the Ham-Hams build a sand castle and recite a spell exactly the way it is written in the book, they are whooshed to the Kingdom. When at last the hamsters reach the bustling Hamja Kingdom of hamsters, the popular King Hamja, the Mini-Hams that they’ve met before in Ham-Ham Land, and many jar spirits called the Mo-Hams appear. A parade begins merrily with singing and dancing! But, the bad magic cat “Sabakunya” appears suddenly, riding the giant sheep monster “Mee Mee”, and starts to trample the town. What a disaster! 
The Ham-Hams flee underground. The Ham-Hams are told of the state of the Kingdom and find that Sabakunya has snatched the King’s daughter, Princess Shera, and is pressing her into marriage on the Kingdom’s Founding Day. Sabakunya is trying to take over the country. Something clicks in Hamtaro’s mind. Princess Shera is without a doubt the princess who appeared in his dreams! Hamtaro wants very much to run to the castle where Sabakunya is, and so he and the Ham-Hams enter the castle. In the castle, they encounter danger after danger, and Hamtaro, pursued by Sabakunya’s henchmen, is separated from others.

In Aurora Village in the high frozen peaks of the mountians, it's getting warmer, and the snow is melting. The Ham-Hams that live their believe that Bijou is their Snow White Princess who can pray for the snow to come back. They send Crystal the snow fairy hamster to summon Bijou to their land. 
Crystal arrives and takes Bijou back, the ham-hams quickly tag along. Meanwhile, pirate hamsters are sailing above the village in their flying pirate ship. The captain of the ship, Hamstern sees Bijou captures her soon after, because he doesn't want her to pray for the snow. While Bijou is held against her will, she is very calm and nice to them even makes some yummy food for them. Hamtaro and the ham-hams come aboard on the ship, Hamtaro learns what Hamstern did to Bijou. He gets really angry, and will do anything to bring her back home. 
Now Hamstern and Hamtaro must compete eachother in the Grand Prix. Where they race in all sorts of ways. Such as racing car. If Hamstern wins, he gets to take Bijou back in his ship. If Hamtaro wins, Bijou can pray for the snow and go back to her friends. 
(Source: hhp.icy-mint.net)

As Laura heads out to summer camp, Hamtaro and Oxnard come across a young girl by the name of Haibi, who's trying to find the ocean. Haibi found a treasure map while searching through the storage burrow and is now willing to find the treasure to help her heat exhausted granny. The Ham-Hams, who are more than willing to help her, pack their things and set out to find the treasure. 
(Source: Wikipedia)

Based on the third Hamtaro game (fourth in Japan), Prince Bo falls from the sky when the rainbow disappears. Now Hamtaro and the Ham-Hams must help him bring back the rainbow. 
(Source: Wikipedia)

Tottoko Hamutaro Anime Dechu! is a direct-to-VHS OVA released on September 15, 1999. This was the first attempt at an animated adaptation of Hamtaro, and consists of four short episodes. 

The VHS was only released as a mail-order from the September 1999 issue of Shogakukan, and given away for free to Shogakukan staff with preschool children. 

(Source: Hamtaro Wikia)

2 new episodes were released among the 2012 re-broadcast of the Hamtaro anime series, "Searching for Memories" and "Panda Goes to Meet a Panda".

A direct continuation of the Tottoko Hamtarou series, introducing new characters.

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