In the animated series, she was voiced by the late Gisela Fritsch in the German version.
Very cunning and manipulative, Mrs. Grindtooth is a knowledgeable, intelligent, and deceptive dragon who likes to torment lesser beings with her power. She is very hotheaded, unpleasant, destructive, obstreperous, and temperamental when she is able to breathe fire in an extremely violent and aggressive manner. One of her most despicable and cruel plans is when she chains the children to desks at her school, where she has barked lessons to them like a commandant. She is also shown to be extremely abusive, defamatory, vituperative, and opprobrious towards the children and her minions.
Jim Button and Luke the Engine Driver
The story begins on a tiny island called Morrowland, which had just enough space for a small palace, a train station and rails all around the island, a grocery store, a small house, a king, two subjects, a train named Emma, and a train conductor named Luke. One day, the postman dropped off a package with a nearly indecipherable address for Mrs. Grindtooth at Sorrowland. After a pointless search for the addressee among Morrowland's few inhabitants, they open the package. To their monumental surprise, there was a black baby inside. After the commotion had died down, the islanders adopted the baby and named him Jim Button.
As Jim grew up, the King began to worry that the island was too small and there wouldn't be enough space for Jim to live on once he was an adult. He announced to Luke that Emma had to be removed. Luke decided to leave the island with Emma, and he decided to come along. They converted Emma into a makeshift ship and sailed off the island in the night, eventually arriving at the coast of China.
When they arrived in Ping, they won the friendship of Ping Pong, who told them that the Emperor was mournful and heartbroken. Li Si was kidnapped and was being held in the Dragon City. Luke and Jim offered their help, and while investigating the circumstances of Li Si's disappearance, they stumbled upon several names which were directly connected to Mrs. Grindtooth, the Wild 13, and Sorrowland. Now Jim and Luke had another reason to go to the Dragon City, located in Sorrowland, and had a confrontational and argumentative situation with Mrs. Grindtooth.
After a long and treacherous journey, they arrived in the Dragon City. Along the way, they make two new friends named Mr. Tur Tur and Nepomuk. Jim and Luke successfully freed Princess Li Si and a largely quantitative number of children, who were kidnapped and sold to Mrs. Grindtooth by a traitorous gang of thuggish pirates called the Wild 13. She chained the children to desks at her school, where she had barked lessons to them like a commandant. Jim and Luke took Mrs. Grindtooth with them as they made their way back on the Yellow River, which began right at the Dragon City. Arriving back in Mandala, they receive a commemorative welcome and were surprised by some startling news. Mrs. Grindtooth was about to turn into the Golden Dragon of Wisdom, and the other inhabitants of Morrowland want them back on the island.
With parting advice given by Mrs. Grindtooth (who was now reformed) and generous assistance from the Emperor, Luke and Jim came into possession of a floating island, which was named New-Morrowland, to served as Jim's future residence. After a benevolent welcome back on Morrowland, Jim and Li Si became engaged, and Jim gets a small train for his own, which he named Molly.
Jim Button and the Wild 13
The story follows the events in Jim Button and Luke the Engine Driver. Life in Morrowland continued as usual for a year until the postman rams New-Morrowland with his mail boat in the dark of night. It was decided that the island needs a lighthouse, but it was too small to support one. Jim remembered Mr. Tur Tur and his ability to appear as a giant when seen from afar, and Jim and Luke decided to invite him to Morrowland to use his special ability as a living lighthouse.
While sailing the oceans with Emma and Molly to get to the desert where Mr. Tur Tur lived, Jim and Luke stop to help out Sursulapitschi and King Lormoral. This led to an extremely precarious and unsafe encounter with the Magnetic Cliffs. The magnetic pull could be turned off and on. When on, they activated a phenomenon called the Sea Glow, which illuminated the bottom of the sea, but also activated the magnetic pull, endangering passing ships. Someone might be found to ensure that none of the ships were endangered while the Sea Glow was switched on. In addition, Sursulapitschi was distressed because her fiancee, a turtle man named Ushaurishuum, has been assigned by her father to refashion the Crystal of Eternity, a task only possible with the aid of a creature of fire, with whom the merpeople were at war.
Using the special propertied of the cliffs' material, Jim and Luke convert Emma into a flying vehicle which they called the "perpetual motion vehicle" due to its unlimited means of locomotion. With it, they crossed the Crown of the World to get Mr. Tur Tur. To their surprise, in the desert, they also encountered Nepomuk for his help in capturing Mrs. Grindtooth. Jim and Luke persuaded Nepomuk to accompany them and took up the post at the Magnetic Cliffs. Unexpectedly, the four met Sursulapitschi and Ushaurishuum at the cliffs, and he and Nepomuk quickly became friends, enabling the recreation of the Crystal of Eternity.
Meanwhile, Molly was abducted by the band of pirates called the Wild 13. Luckily for Jim and Luke, Mrs. Grindtooth formerly awoke as a Golden Dragon of Wisdom in China and could help them out with information and told Jim how to find out about his origin. With the help of the Emperor, Jim and Luke – and Princess Li Si as a stowaway – started their journey to meet the Wild 13 and rescue Molly. They encountered the pirates, who proved to be too much for them in battle. Molly was lost at sea, and all but Jim were captured and brought to the pirates' base, Castle Stormeye, a pinnacle of rock within the eye of an interminable hurricane.
Jim invisibly managed to sneak into the pirates' fortress, overpowered them with a trick and some luck, and became their leader. As it turned out, Jim was the last descendant of Caspar, the third of the Three Kings, whose heirs were doomed to remain homeless after Mrs. Grindtooth had sunk their kingdom beneath the ocean 1,000 ago. Only the sinking of Castle Stormeye would raise it back to the surface. In the end, the Wild 13 sacrificed their fortress, Jim's old kingdom reappeared – and to everyone's surprise, Morrowland was located at the top of the realm's highest mountain.
All of the families had rescued from the Dragon City came to live in the new country. Jim married Li Si and received Molly from the merpeople, her iron frame transformed into the Crystal of Eternity. The Wild 13 were reformed by their sacrifice and remained in Jim's kingdom as its protectors and royal guards. Meanwhile, Mr. Tur Tur went to live on Morrowland as the world's largest lighthouse.