Readers of this column know that from time to time I go in search of what makes a particular writer of mass commodity fiction so vastly popular. I set about the search again with Belva Plain's 20th novel, Her Father's House, (Delacorte, 342 pages, $25.95) -- aware that there are 25 million copies of Plain's books in print.

From the outset, Plain writes in a kind of studied near-graciousness, in a narrative voice that seems almost Edwardian. There are very specific descriptions of people -- not only of their hair, their eyebrows and their clothing, but also the details of the world around them. It's the sort of pleasing brush-stroke specificity that the culture theorists claim has been driven out of literature by movies and television.

The main character is one Donald James Wolfe, who, in 1968 when the book commences, is a 25-year-old freshman associate in a white-shoe New York law firm. A North Dakotan who grew up on a farm, he is diligent, ambitious, dutiful, favored by a name partner. Quickly the tale begins to rattle with cliches.

Donald -- people go by first names in this narrative -- meets Lillian, a secretary, in a Manhattan park. In 31 hours they are in bed and involved -- though with no detail that would distress your most lavender-sacheted maiden great aunt. They move in together in a new apartment. All is hunky dory. Donald reaches his sixth year in the firm, gallivanting globally with top partners, executing international litigation and negotiation of the most sophisticated sort.

He is made partner and immediately proposes to Lillian, whose past is a deep mystery. Even though they've lived together for some six years -- reader, suspend disbelief! -- she has never discussed her family, ostensibly on nearby Long Island, except to say her parents are dead and the other relatives are boring. He has never met her boss, a high-flying lawyer for glitterati, who gives them a very expensive Danish silver service for 12 as a wedding present.

Soon on, their marriage sputters. She grows demanding, avaricious -- a yowling social climber among New York's tawdriest instant rich. The level of naivete of this guy is never examined, explained or made believable. This is a comic book in prose.

Leapin' lizards, Sandy!

Lillian bonds with this ostentatious, superficial, sybaritic crowd. She becomes pregnant against her intent. As Donald begins to discern that all is not well, Plain writes, "He looked at her. Even though the afternoon sun was falling full upon him, he felt a wave of chill. We don't know each other. I don't know her, he thought. And it was as if these last few lovely weeks had never happened." They'd been together six years. This perception is delivered without prior context, as a cartoon panel.

In the third month of her pregnancy, they are on a grand tour in Italy, where she had spent considerable, more than somewhat mysterious, time before they met. Now she defiantly sleeps with at least one other man whose name she declares herself proud not to know.

Inevitably, Donald and Lillian are divorced.

Her ex-boss's ailing wife has conveniently died and he marries Lillian. Donald turns up at the hospital the day the baby is born. He gives Lillian uncontested full custody of the child, ambivalent about the whole thing -- a New York international corporate super lawyer living like a hayseed high school sophomore. Ex-boss surrounds Lillian with luxury and a nanny for the kid, Bettina.

Holy paterfamilias, Batman!

It's corny. It's superficial. It's illogically conceived. It is dramatically ridiculous. But it moves swiftly. There is an energy and flow about the action, the clipped dialog. It kept me going when I expected to have to fight to read on -- the dynamics of a cartoon sequence. There is economy of motion. By keeping Lillian's past and proclivities murky, sinister and unraveling them in bits and slivers, Plain sustains a tension. But overshadowing it all, there is the unrelenting implausibility of everything.

Donald sees his daughter in the park with her nanny, and begins to obsess. Learning that Lillian has been dropped by husband number two and has taken up with rich Eurotrash, Donald goes bonkers. I'll kidnap the baby, he decides, run away forever, change identity and all else about life. No alternative is considered.

The girl's 2 when he snatches her. He drives to a Georgia farm village, where -- lo and behold! -- he just happens to have the address of a nice lady he once sat next to on an airplane. She -- Kate -- and husband just happen to have a farm that desperately needs help -- and an empty cottage nearby. Father and child, with earnest joy, become part of farm and family. Donald -- now called Jim Fuller -- charms the local bankers, reorganizes the place, saves the farm, makes everybody prosperous. He becomes a key citizen. Kate's husband, Clarence -- I would not lie to you (he might have been Hiram, I suppose, or Bubba) -- becomes terminally ill, dies. A year passes and -- well, love and marriage follow. But that's not the final comic-book frame.

Glorioski, Zero!

"People don't want much, he thought," Plain writes. "When you come down to it, what we really need is a fairly simple thing, just not to be afraid of tomorrow morning."

Years of tomorrow mornings pass. Kate has been told all, but not the kid -- renamed Laura. She is utterly unaware of her origins, and her dad has spun tales about a tragic death of her mother. Kate insists Jim will never be tracked down and arrested, though his anxiety about kidnapping prosecution is unrelenting. Twenty years of bucolic comfort and minor domesticity pass. Laura goes to medical school in New York.

One thing leads to another. Cops turn up at the door, extradite Fuller to New York. He goes into a complete funk, declares his case is hopeless and consigns himself to 20 years or more in prison -- an absurdity supported by a couple of ostensibly licensed and experience lawyers. Laura gets into a hate-filled rage. Disaster all around. Stuff happens. Then, suddenly, there is a deafening flutter of dei ex machina. Everybody lives happily ever after.

Alas, the idyllic ending negates any small virtues of Plain's narrative skills. After navigating all 342 pages of this novel, I cannot recall ever having read a less artful, a more predictable, a more sordidly sentimental book.

Don't have a cow, man!