MORE THAN YOU KNOW, by Beth Gutcheon, William Morrow, New York, 1999, 288 pages, $23.

At 17, it seems like no one understands how you feel. One day you’re laughing hysterically, the next you’re soaking your pillow with tears. Your body is doing all sorts of weird things that you don’t want to talk about. Just when you think it can’t get any worse, you fall in love and your emotions go haywire. And your parents just don’t get it.

Author Beth Gutcheon does get it. Her latest book, “More Than You Know,” tackles the rough terrain of first love, daughter-stepmother relations, divorce and loss. As if that weren’t enough, she weaves it all together with an extraordinary ghost story set against the backdrop of a Maine island.

“[Teen-agers are] being yanked around by such powerful emotions, and they’re absolutely real and strong,” Gutcheon said from her New York home. “For older people who are trying to understand them, it’s like they’re inhabited by demons.”

Gutcheon, who has a year-round home in East Blue Hill, set the book in the fictional town of Dundee and the outlying Beal Island. The villages in the book are a melange of Hancock County towns, and the story centers on a haunted house that has been moved from the island to the mainland.

“Ghost stories are usually short-lived because ghosts are site-specific,” Gutcheon said. “But as you know, in Maine, they move houses around.”

Moving the house allowed her to “extend and deepen the story,” she said.

“More Than You Know,” tells the love story of Conary Crocker, the town rebel, and Hannah Gray, a Boston girl whose mother grew up in Dundee. Her mother died when she was 3, and Hannah’s father stayed close with his former in-laws even after he remarried. At his suggestion, Hannah’s stepmother has rented a house in Dundee for the summer while he stays in Boston.

Hannah, now an old woman, has decided it’s time to tell the haunting (and haunted) story of that summer. She begins forebodingly, saying “Somebody said, `True love is like ghosts, which everybody talks about and few have seen.’ I’ve seen both and I don’t know how to tell you which is worse.”

The house Hannah moves into, formerly the schoolhouse on Beal, was moved to the mainland years ago. When it moved, an unrelentingly angry ghost moved with it. Her stepmother doesn’t see the ghost and doesn’t believe Hannah, and the already tense relationship between them worsens.

Desperately trying to get out of the house, Hannah starts hanging around town, where she meets Conary. Soon after, they fall in love, and soon after that, the ghost starts terrorizing them both.

Alternating chapters tell a parallel story of a couple who lived on Beal a century before Hannah and Conary. As the murderous substory unfolds, it becomes clear that someone from this chilling past is haunting Hannah and Conary — we don’t find out who until the last page.

I devoured the fast-paced, gripping story in several hours. Gutcheon dangles clues of what’s to come at the end of each chapter, making “More Than You Know” hard to set down. I came to care deeply for Hannah and Conary and to loathe Hannah’s smothering stepmother. The ghost is real enough to touch — though I wouldn’t want to.

Gutcheon captures the young lovers’ fresh, intense emotions so realistically that it made me long to be 17 again. The story is enough to make even the biggest skeptic believe in ghosts — those that haunt houses and those that haunt the human heart.

The author also has a firm grasp on the Maine coast, its people and its stark beauty. She doesn’t dumb-down the locals or throw in a lot of “ayuhs” or “lobstahs” or “cahs” as authors who write about Maine are wont to do. It’s refreshing.

In under 300 pages, Gutcheon has woven two complex tales that examine convoluted family relationships and the mysteries of human nature. She ties everything up, but the end left me wanting more — not that the story was lacking, I just wanted more time with the characters. I grew to know them and I wanted to stay with them a little longer.

But, as Gutcheon said, it’s hard to keep a ghost story going too long. Regardless, Hannah’s story will haunt you long after you put the book down.

Beth Gutcheon will sign copies of “More Than You Know” from 2 to 4 p.m. Saturday at Port in a Storm bookstore in Somesville. For information, call 244-4114.