That Old Ace in the Hole, by Annie Proulx. Scribner. 384 pages. $26.

Annie Proulx is our literary explorer, venturing forth into mostly unchartered terrain (Newfoundland in The Shipping News, Wyoming in Close Range), then emerging with her notebook and imagination re-stocked with quirky facts, eccentric characters and memorable tales.

This time, Proulx has set her creative sights on the arid and forlorn landscape of the Texas and Oklahoma panhandles, the states "stacked like dirty pots in the sink, their handles touching." This is land "as level as a runway," where corporate hog factories have replaced cattle ranches and where people cling to an unforgiving way of life for reasons that aren't always clear to outsiders.

"You think it's just a place," explains one character in this book. "It's more than that. It's people's lives, it's the history of the country."

The trouble is, Proulx has so much she wants to share -- history lessons, geographical descriptions, concern for the environment -- that she sometimes forgets to push the narrative along. Rather than wonder what will happen next, readers may ask themselves if anything will. The pace often falls on the slow side of plodding.

That said, the writing is so sharp and fresh, it's easy to overlook everything else. Proulx writes as if she invented the language, creating lingering images with a few deft strokes. She could make a Denny's menu worth reading.

Nobody describes faces as well as Proulx does. There's Sheriff Hugh Dough (Proulx has a soft spot for cartoonish character names), whose face revealed "a sharp Aztec nose, fluffy black hair and black eyes like those in a taxidermist's drawer."

There's Rella Nooncaster, "a sallow woman as thin as a chopstick, her white hair in a spiky butch cut."

There's Bob Dollar, the protagonist, "a curly-headed man of 25 with the broad face of a cat, pale innocent eyes fringed with sooty lashes."

When he was 8 years old, Dollar was abandoned by his parents and raised by a kind-hearted uncle. Now an aimless adult, Dollar latches on with Global Pork Rind and is sent by his boss, Ribeye Cluke, to the panhandle to search for suitable locations for future hog operations.

He lands in Woolybucket, Texas, and rents a bunkhouse on the Busted Star Ranch from a local historian. Dollar tells the townsfolk he's looking for locations to build luxury homes because most people scorn the hog factories. In other words, he's an imposter. They see right through him anyway.

You will not look at a slice of bacon the same way after reading Proulx's descriptions of corporate hog farming, which has done more to change the culture of rural life than anything since electricity arrived. She makes a credible case that these massive pig factories are not only ruining the air and water, they are producing pork that tastes bad.

But here's the point: This book feels like Proulx is more interested in making a case than telling a story. Like most of the characters here, Dollar basically serves as a vehicle for Proulx's frequent tangents into all she has learned, on subjects that include windmills, barbed wire, the oil industry and bison. The information is frequently fascinating, and always well-written, but it tends to detract from our willingness to believe in, and care about, the characters. Just because they're eccentric doesn't make them real.

If Bob Dollar feels any moral misgivings about lying to the people he eventually comes to like and respect, he does not share them. For that reason, the ending feels improbably sentimental, much like Proulx's vision of bison roaming on the restored panhandle prairie. But as one character says, "The frontier character means not giving up on anything after it fails."

Anything that Annie Proulx writes is worth reading, but it will be surprising if the people who found The Shipping News so powerful will feel the same way with That Old Ace in the Hole. This is a case in which the lyrical parts are greater than the emotional whole.

Ken Fuson, a former staff writer for The Sun, has been a reporter for more than 20 years. He now works at The Des Moines Register.