Navigating the murky backwaters of an American literary icon

Debates as to the identity of America's greatest literary work generally boil down to two choices: Herman Melville's "Moby-Dick" or "The Adventures of Huckleberry Finn" by Mark Twain. Perhaps exhausted by the endless argument, in recent years writers have taken matters into their own pens, expanding their favorite stories as they pay homage.

Consider Sena Jeter Naslund. She embarked on an ambitious bit of literary derring-do with "Ahab's Wife," her 2000 bestseller playing on the fringes of Melville's masterpiece. It explored the back story of the Pequod captain's beloved as she languished in Nantucket.

Now comes debut novelist Jon Clinch with Finn, the logical counterpart to Naslund's book. It explores the depravity of young Huck's father, a violent drunk whose racist notions rage against interracial carnal urges.

"Finn" brims with tension, fueled by sentences as taut as a cane pole wrestling a catfish in muddy waters. Considering the heady literary terrain Clinch hopes to master, the novel succeeds better than anyone other than its author could have expected. It offers a jolting companion to the mischievous antics of "Huckleberry Finn."

Clinch proves effective at simultaneously embracing and distancing himself from Twain's celebrated novel. He takes a brief description of Huck's despised "Pap" – discovered by Jim as a corpse in a room afloat with bizarre contents – from Twain and creates a brooding narrative that fits with the earlier novel's events and chronology even as it stakes out much darker territory.

Twain leavened the biting satire and gradual discovery of racial inequality in his novel by telling his story through the youthful Huck's first-person voice. Clinch's tale unfurls in the hands of an omniscient narrator with a blunt, clear-eyed adult perspective.

Pap Finn (we never learn his first name), as Clinch tells us early on, "drags a divisive trail of misery behind him as a mule drags a plow."

Few details of Pap Finn's life emerge in Twain's novel. Clinch takes those scattered references and fleshes out an engrossing tale of corrosive generational warfare. Pap, it turns out, came from a prominent small-town family straight out of Tennessee Williams.

The patriarch, the powerful local judge James Manchester Finn, rules with tyrannical cruelty. Pap and his brother, Will, emerge, unsurprisingly, as miserable adults. Will manages an air of adult convention through his law practice. Pap fails even that. Instead, he plummets into poverty and alcoholism – the blackest of black sheep.

Clinch picks up the narrative thread as Pap commits a Hannibal Lecter-style murder. He dismembers his young black mistress – this after an audacious episode of miscegenation – in gruesome fashion before sending her corpse down the Mississippi. But those horrors pale next to Pap's frightening blend of crazed logic and cruel calculation. His motto might best be stated as, "Malice for all."

Finn curses the judge, his neglected son, women, children, traders, bartenders, and anyone else in his orbit. As a town doctor says of Finn, "The only way you'll ever improve him is with a pistol."

Clinch keeps Pap from devolving into caricature by delving into the guilt and psychoses hounding him.

Finn drinks himself into a stupor every night in a failed attempt to forget the nightmares of his own actions – and those of his family. Like a deranged Faulkner, he seeks contrition by chronicling his acts in a crude narrative scrawled on his bedroom walls.

Whiskey represents the lone pleasure in Finn's life. He makes his living from the river, bartering his daily catfish haul for minimal groceries and as much whiskey as he can afford. Finn spends much of his time in a backwoods hut with a blind bootlegger named Bliss, whose life is anything but.

Clinch writes with a grim sense of foreboding. He never shies from the ravages borne and bred by the damaged souls drowning in the midst of the mighty Mississippi. As with Twain, Clinch makes the river a prominent character, a presence that "steams like slow soup in the cool morning."

Grab a raft and test the waters, but beware. This river ride disturbs even as it enchants.

• Erik Spanberg is a freelance writer in Charlotte, N.C.