|The Source of Magic|
|Cover artist||Doug Beekman|
|Publisher||Del Rey Books|
|Publication date||February 1979|
|Media type||Print (Paperback)|
|Pages||326 pp (paperback 27th printing)|
|Preceded by||A Spell for Chameleon|
|Followed by||Castle Roogna|
At the opening if the book, Chameleon is very pregnant and in her ugly-but-smart phase while Bink is chafing at the stressful home situation and general lack of productivity.
Queen Iris is hosting a ball in celebration of King Trent's coronation which involves a contest. Millie, the ghost-maid wins the contest and its prize of one free answer to any question from the good magician Humfrey.
Millie wants to know how she may live again. Humfrey provides the required information (remotely via magic mirror) and a search for her body becomes a new contest in which finder will win a date with Millie. Bink finds her body transformed into a book (topologically shaped, not strictly transformed) in the king's library and Millie is returned to life.
King Trent helps Bink avoid the awkward situation of winning a date by sending him away to find the source of magic (by way of Humfrey's castle) with Chester Centaur and Crombie the soldier as companions. All three have women problems.
Together they travel to Humfrey's castle, narrowly escaping an encounter with a dragon and nicklepedes. Bink is forced to win entry to the castle, and Humfrey reluctantly helps Bink free of charge, since he is on the king's business. Humfrey then decides to join the expedition, bringing Grundy the golem, along with a myriad of spells and other items conjured into bottles and vials.
The extended party sets off into the wild and meet Crunch, a vegetarian ogre who is willing to provide a place to stay for the night. During the evening, Grundy inadvertently releases Beauregard, a lesser demon, from one of Humfrey's bottles.
They continue on their journey and find the Magic Dust Village, an all-female village dedicated to spreading magic dust across Xanth, but this is not the ultimate source of magic. They learn that the village men have all been lured away by the siren. Shortly there after, the traveling party are lured into the jungle by the siren's song as well.
Next, the searchers must pass through the Region of Madness and trek into the lake of the Curse Fiends. Humfrey, Crombie and Grundy submit to being conjured into one of Humfrey's bottles, while Bink and Chester use magic pills to walk through the lake and enter the under water lair of the curse fiends.
Bink and Chester, with the others in tow, jump into a vortex in the lake, around which the fiends have built their city. The vortex takes them into the underworld, and closer to the source of magic, but Bink loses the bottle containing his friends in the process.
Searching for his friends, Bink inadvertently drinks from a love spring and falls in love with Jewel, the nymph of Jewels. Jewel takes Bink and Chester to the demons where they once again meet Beauregard, who helps direct Bink toward the missing bottle. Bink, Jewel and Chester find it in the pool of the brain coral.
The brain coral, who has been opposing Bink's quest all along, uses Grundy to conjure Humfrey and Crombie from their bottle, forcing them to do its bidding. A fight ensues. During the scuffle, Chester falls into the brain coral's pool and Crombie is critically wounded. Bink is finally victorious and negotiates for the brain coral to let Humfrey to show him the source of magic. Crombie is healed and re-bottled.
Bink learns that the true source of magic is a major Demon named X(A/N)TH, who has been isolated according to the rules of a complex inter-Demon game. Bink wills the Demon free, satisfying the game's rules for his release and X(A/N)TH (the Demon) quickly and violently leaves Xanth (the land), taking all his magic with him.
In the confusion that follows, Humfrey is lost and Bink returns to the surface, with help from Jewel, to find a much more mundane Xanth. On his way back to the king, Bink meets Chester's mate Cherie. She convinces him to return with her to find Chester and Humfrey.
They arrive to find that X(A/N)TH has just returned (for "an eon or two") while he re-strategises in light of changes to the Demon game that have occurred while he was in isolation, thus returning magic to the land of Xanth and ending what will later be called the time of no magic. X(A/N)TH provides Grundy a real body, rescues Humfrey and Chester; and after testing his mettle, is persuaded to give Bink a reward for releasing him.
The party returns home, where Bink learns that his newborn son (to be named Dor, but not in this book) has already manifested the magician-class talent of making inanimate objects speak.