"St. Lucy's Home for Girls Raised by Wolves," Karen Russell's 2006 short-story collection, was a revelation. Her insistent and insinuating voice sprang from the page as if propelled by a pair of strong haunches. That voice is back in full force at the beginning of Russell's debut novel, "Swamplandia!" -- except this time those wolves' haunches have been replaced by the awesome snap of an alligator's jaws.

Narrator Ava Bigtree is the youngest in an achingly real family with a fictional back story, her paternal grandfather having rechristened their Caucasian clan as the vaguely Seminole "Bigtree" to add authenticity to his alligator-wrestling franchise. That franchise, Swamplandia!, is set on a very minor Key, a tiny island that visitors reach from mainland Florida by ferry, otherwise leaving the Bigtrees -- father, only ever known as Chief; mother Hilola; son Kiwi; daughter Osceola, or "Ossie," and the youngest child, big-hearted Ava -- very much isolated in their own private world.

At one time, Ava tells us, Hilola Bigtree (sporting "a modest green bikini") would dive into a pit full of 'gators, known collectively as "the Seths." However, when readers meet the Bigtrees, all of them (except Grandfather Samuel, who languishes in partial dementia on a houseboat-cum-nursing-home) are reeling from losing Hilola to ovarian cancer. Kiwi leaves for the mainland, as he longs for real school and a job. Chief Bigtree takes vague care of his daughters, then suddenly and inexplicably leaves them alone.

Ossie, 16, is more than a little troubled -- she's not just hearing voices and seeing things, she's actively in love with a "ghost." Disaster follows when she, too, disappears, supposedly heading off with him to the "other world." Ava, 13, with no family and longing for a quest, decides that setting off to look for Ossie with an odd stranger wearing a coat trimmed with feathers is a fine idea.

And that is probably both more than and yet not enough plot summary. Russell has crammed her debut with all sorts of narration: Ava's first-person is interspersed with a historical piece purporting to be about Ossie's ghost lover, a longshoreman on a 1930s swamp dredge, and quite funny and poignant chapters about Kiwi's baby steps as a mainlander working at the World of Darkness amusement park. She's also stuffed it with characters, so many that sometimes I felt about them like Kiwi's tomcatting colleague Yvans does about his 10 children -- he can't always remember their names.

Most interesting, she's stuffed it with meaning. Russell's always compelling authorial voice and her nearly offhand skill with symbolism transcend a couple of plot wobbles. In particular, Ava's presence at the birth of and her care for an unusual baby, "Seth," will remain with readers for a long time as a metaphor of -- well, no spoilers. You should read "Swamplandia!" Some muck goes with the territory, and you'll happily wallow in it.

Bethanne Patrick is a freelance critic and author who lives in Arlington, Va. You can follow her on Twitter @TheBookMaven.