I have to hand one thing to Piers Anthony: He managed to take a single plot element, the disappearance of Good Magician Humphrey, and make it last for five novels, barely advancing the search for the Good Magician in each book.
After her brother Dolph looked for the Good Magician Humphrey in the previous book and came back with two fiancees, Princess Ivy decides its her turn to go look for the Answer-providing Magician. After stealing back a magical mirror from a magical Com-Pewter, she invokes the Heaven Cent and ....
Enter Grey Murphy, stage left. Residing in magicless Mundania, he has managed to obtain a computer program that procures girlfriends for him. And its latest procurement? No prize if you guess Ivy. Following the by-now standard Xanth formula, they undertake a journey (back to Xanth) and fall in love along the way.
But it's a good journey. Piers Anthony made two very, very good decisions with this novel. First, he abandoned the juvenile tone that infested earlier and later entries in the Xanth series. Second, after umpty-ump Xanth novels made tangle trees, ladies-slipper bushes, and other magical marvels seem mundane, Anthony chose to approach much of novel through an outsider -- Grey Murphy.
Even as he confronts wonder after wonder, Grey Murphy refuses to believe in magic. A sailing mountain? Special effects. Invisible giant spouting a river of blood? Food coloring. A half-human, half-equine centaur? A robot. A hate spring? Ordinary water, backed by a strong superstition that it will make people hate each other.
Despite his disbelief in magic, Grey Murphy is nonetheless the typical Anthony protagonist, with a code of ethics that uniformly matches every other protagonist we've seen out there. Not that I mind ethical characters, mind you; it just gets tiresome when, after a dozen books, all the good guys display identical codes of ethics. Kind of ruins diversity of characters.
The plot continues, with Grey having to meet a certain challenge to successfully assert a claim to Ivy's hand in marriage, journey all over Mount Parnassus, and overcome a rather nasty oath that's been forced on him ... but things might just turn out well for this happy couple, right? Right??
If you would like to inflict the remainder of this series on yourself, this book is a very good jumping-on point. Grey Murphy's unfamiliarity with the land of magic makes him a good proxy for an unfamiliar reader, but the book's other flaws (uniform characters, linear plotting) keep it from a perfect rating.