Yearning to Be Free of the Mind’s Cages : THE WOMAN AND THE APE by Peter Hoeg; Farrar, Straus & Giroux; $23, 272 pages

“Grown up,” says the woman to the ape, “is something you become only once you are free.” “Free,” the ape says, peeling an orange.

Freedom, it so happens, is a bone that Peter Hoeg, 39, born, raised and now living in Denmark, has chewed on in each of his books, whether it is freedom from society, from culture, from money, from tyranny or from self-hatred. He is one of those authors who it is worth standing by, reading each book, following each train of thought, for better or worse. And because he writes books full of ideas like the one above, books that wrap themselves around a reader’s psyche so neatly, filling, for a time, every nook and cranny, they are strangely custom-made. Preference depends utterly on what bone you happen to be chewing on at the time, or pretending not to chew on, or avoiding completely.

I should also say that each book is also stunningly different from the last in structure, despite continuous trains of thought. “Smilla’s Sense of Snow,” published in 1993 in English (Hoeg writes in his native Danish), is a literary thriller revolving around the strange death of a child but, in the end, most memorable for its main character, a half-Danish, half-Inuit Femme Nikita named Smilla Qaavigaaq Jasperson. “Borderliners” is set in a Danish school that is conducting cruel if banal experiments on children. In this book, Hoeg somewhat abandons plot for interactive pondering with the reader on the nature of time, the persecution of children, the welling-up of innovation and creativity in the face of adversity. “The History of Danish Dreams,” which was translated in 1995, is a magical realist story of four Danish families.

“The Woman and the Ape” takes on the question of human nature, our wild nature, what it has become, the various ways we repress and pervert it, and what it might mean to find it again.

Madelene Burden is 30 years old, Danish-born, and doing her best to destroy herself with a daily concoction of 99.6% alcohol and distilled water. Her husband, Adam Burden, is the director of London’s Institute of Animal Behavioral Research, and with the help of his Cruella DeVil-type sister, Andrea Burden, is on his way up. Madelene and Adam live in the family seat, Mombasa Manor, in that most corrupt of cities, London. Adam likes making love with his wife (though he never stays the night in her room), but is completely indifferent to her inner life. He’s a busy guy.

Into their lives comes Erasmus the ape, who has escaped from a poacher’s ship as it prepares to dock on the Thames. Captured by Adam and a team of evil scientists, Erasmus is brought to Mombasa Manor, where he meets Madelene.

“She had the feeling [on meeting Erasmus for the first time] that she was being unmasked, spied on, scrutinized, as though it saw right through her, saw her naked, devoid of makeup, and, worse still, saw her pathetic inner self, her insecurity, her worthlessness.”

Those readers who dream of being known, understood, unmasked, listened to, who like their characters revealed, who appreciate turning points at which the layers of unrecognizable junk are hurled aside will, after this first meeting of the woman and the ape, lean into the book, develop a tropism for the book, in hopes that the two escape their prisons and start anew.

In her effort to free Erasmus, Madelene uncovers at least three women living inside her, all long-subdued by alcohol and all clamoring to play a role in her escape. In fact, each character in this novel has at least two other characters locked away inside. They don’t all get free, but Madelene does, triumphing by her wits alone, against the Animal Welfare Foundation (a high society enterprise run by Cruella / Andrea) and the Institute of Animal Behavioral Research.

Madelene and the ape enjoy a brief period in hiding, during which they fall in love (“Hurts,” says the ape describing this condition, “in heart”), wrap around each other in all kinds of ways (“Madelene had read in books that one can expect to become one with the person one loves. But she had never become one with Adam. She had become two. She had split into two people . . .”) and eventually come down from the trees to try to prevent Adam from unveiling his discovery of the ape at a black-tie dinner.

At this point, the novel takes some unpredictable turns; civilization itself is unmasked and crumbles like Don Quixote, but Madelene and the ape emerge from its smoldering ashes, promising hope for humankind. It’s a creation story, of a kind, written by an author with some vantage point on humanity--lofty perhaps, but free.