Howl Jenkins Pendragon is a powerful wizard living in the land of Ingary. Originally Howell Jenkins of Wales, he was part of a loose fraternity of wizards on Earth. He made his way through a magical portal to Ingary, where he became known and respected as one of the most powerful wizards there was. He owns a moving castle, and spreads rumors about himself to retain his privacy, opting to be alone and hiding from all conflict. He is twenty-seven years old in the first book, and thirty in the third.
Howell Jenkins was born to an ordinary family in modern-day Wales. However, he himself was anything but ordinary. Gifted with a natural talent for magic, he began studying it. Even in college, he wrote his thesis on magic, and joined a group of other gifted magicians on Earth. Somehow, he managed to create or find a portal to Ingary, where he moved to live mostly permanently. Still young, he took up tutelage under Mrs. Pentstemmon (Madame Suliman in the movie adaptation). He became her last pupil, and one of her favorites. His natural gift for magic showed, and he was quite powerful. Howl is a wizard in the land of Ingary and he has several names, he is known as Wizard Howl in Market Chipping, "Wizard Pendragon" in the capital Kingsbury, and "Jenkin the Sorcerer" in lower-class Porthaven.
One night on the Porthaven Marshes, he caught a Falling Star named Calcifer and made a contract with him. Feeling sorry for the unfortunate star, Howl gives him his heart, binding them together, and allowing Calcifer extended life, while boosting his own magical power. After doing so, Howl quit his apprenticeship and became a hermit. He dyed his hair and spent all his money on make-up and clothing, and spent his days wooing young ladies until they fell in love with him, then dismissing them. During this time, Howl found Michael Fisher sleeping on his doorstep, and invited him in. Howl was impressed by Calcifer's reaction to Michael. Though he never explicitly told Michael he can stay, Howl allowed him to live in the castle, eventually making him his apprentice. Also during this time, Howl courted and then dumped the Witch of the Waste, who put a curse on him.
Howl occasionally does work for the King's army, but avoids contact with them as much as possible. It is during one of his outings to find a young woman that he first meets Sophie Hatter. He first meets Sophie on May Day before the Witch of the Waste casts an aging spell on her. Days later he gets back to the castle and is surprised to find an old lady cooking on Calcifer. Despite Michael and Calcifer's complaints he lets Sophie clean the castle. Although he has been gathering clues about Suliman's disappearance, Howl is concerned the king wants him to find Prince Justin. He gets Sophie to pretend to be his mother to blacken his name to the king but the king is more impressed than annoyed, and hires him as the Royal Wizard.
Howl battles with the Witch of the Waste after Mrs. Penstemmon's funeral. Now that the Witch knows he lives in Porthaven, he decides to move the castle to escape. Taking Michael and Sophie's wishes into consideration, he takes the hat shop in Market Chipping so Michael stays close to Martha, ordering Calcifer to find a nice house with lots of flowers for Sophie. Howl helps in the shop and discovers the dog is a bespelled human. He restores him to his human form and suspects he is made of Wizard Suliman and Prince Justin's body parts. He uses Sophie to get information out of him. As the curse is about to be fulfilled, Howl gets drunk, but he also arranges for Sophie's family to visit. When Sophie falls in the Witch's trap, he raises a wind to bring her back and explains his motives. His honesty seals his fate and the Witch's fire-demon, in the shape of Howl's nephew's English teacher, gets hold of Calcifer and squeezes the heart Howl had given Calcifer to keep him alive. Howl collapses but Sophie saves him by giving him his heart back. By breaking Howl's and Calcifer's contract, Sophie returns to her true age. Howl gets rid of the witch's fire-demon, and by doing so restores Suliman and Prince Justin to their true forms, and asks Sophie to marry him.
Castle in the Air
Howl has married Sophie and she is pregnant with their first child, Morgan. While Howl is casting a divination spell he discovers that a djinn intends to steal the castle from them. He sends Michael and his new apprentice away. He attempts to send Sophie to Wales to stay with his sister Megan Parry, but Sophie refuses to leave him, saying that she'll be of more use in the castle. She asks him to cast a spell so that the djinn can't see her. Howl and Sophie argue about that; while they are still arguing, the djinn arrives, and Howl quickly turns Sophie into a cat. Sophie is then somehow thrown from the castle and ends up in the mountains north of Kingsbury.
Howl is turned into a Genie and Calcifer into a magic carpet. Howl is cursed so that he is unable to tell anyone that he is under a spell and no one is able to recognise him. Both Howl and Calcifer find themselves in the hands of Abdullah, a carpet merchant, who has also lost his true love to the djinns. Howl promises to grant a wish each day to Abdullah, although Howl uses his powers to cause as much trouble for Abdullah as possible. He later encounters the cat Sophie, who is named Midnight by Abdullah's companion the soldier, and finds that she has given birth to Morgan who is a kitten. Although Midnight is unaware of the Genie, he notices her and occasionally suggests he knows Sophie and Morgan. When Morgan is turned back into a baby, the Genie takes him to the castle in the air so he can keep an eye on him. Once the djinns are defeated, the Genie is turned back into Howl and he is reunited with Sophie, Morgan and Calcifer.
House of Many Ways
In House of Many Ways, Howl is first mentioned as one of several royal magicians. His wife Sophie comes to High Norland to help find the lost gold for King and Princess Hilda. Howl soon appears, in the form of an adorable boy named "Twinkle". In Twinkle form, Howl looks like a boy with curly blonde hair, big big eyes, and an annoying lisp. Although he knew he hadn't heard of another Royal Magician helping another nation, he came to help Sophie, who is not amused by this idea. Twinkle also brought Morgan, the son of Sophie and Howl, and Calcifer, the fire demon. During one of Charmain Baker's visits (the book's main character), Twinkle climbs onto the roof to tell her something important. It turns out that they need help with some documents, the same ones that Charmain was helping the King with. He told Charmain that helpers have a spell to help, and write it for him and Sophie. Charmain helps both of them. It is then shown that Prince Ludovic, the only one who can claim the throne, had nine cousins who had died quite painfully.
At the ending of the book, it turns out that Prince Ludovic was the one who was stealing much of the gold from the Royal Treasury for his own castle, but it also turned out that Prince Ludovic is a creature called a Lubbockin, a human/Lubbock being. Its father, a Lubbock, wanted to take over High Norland, and use Prince Ludovic as a puppet king. Thinking that it was Twinkle who was important to Sophie, not knowing that it was in fact Howl, he tried to harm Twinkle. Both Sophie and Charmain chase after two other Lubbockins, leaving the King, Princess Hilda, Prince Ludovic, Sim, and Morgan in the castle.
When they return, Prince Ludovic had captured Morgan, and he and a colorless man, whose name is unknown, get away, with Twinkle in tow. When the main group catch up, they find the four in the Royal Parlor, and Prince Ludovic is strangling Morgan. Howl stops this, by both switching his place with the three year old, and returning back to his normal form. He and Calcifer transform the two lubbockins into rabbits, since one of them had gotten his foot smashed by the hidden gold, and was hopping around, getting Calcifer to think about rabbits. In the end, Howl explains what happened to the gold, and where the Elfgift was. The ending shows Howl, Sophie, Morgan, and Calcifer leaving, with Morgan calling out to Twinkle.