Robert B. Parker, who died Monday in his Cambridge, Mass., home at age 77, spent his final moments doing exactly what he'd done for almost four decades: sitting at his desk, working on his next novel. He didn't concern himself with looking back. Instead, he wrote, and in the process irrevocably altered American detective fiction, forging a link between classic depictions and more contemporary approaches to the form.

Parker produced more than five dozen books in a variety of styles, including westerns, historical fiction, a marriage memoir and a nonfiction account of horse racing.

But the bulk of his writing revolves around Spenser, the one-named, Korean War vet detective first introduced in "The Godwulf Manuscript" (1973).

That novel, which Parker wrote two years after publishing his Boston University doctoral thesis on the violent heroes of Dashiell Hammett, Raymond Chandler and Ross Macdonald, is a clear pastiche of those authors' works. Parker's biggest debt, though, was to Chandler, whose detective, Philip Marlowe, inspired Spenser's poet-inflected surname, his noble quest for justice and his desire to save women from miscreants.

Marlowe as muse

The Chandler connection ran so deep that Parker completed the unfinished Marlowe manuscript "Poodle Springs" in 1989 and a year later published "Perchance to Dream," a sequel to "The Big Sleep."

Still, by the early 1980s, Parker had moved away from imitation and into the realm of imitated.

"Looking for Rachel Wallace" (1980) and "Early Autumn" (1981) hold up as among his very best novels, featuring kidnapping-centered plots that move at an express-train clip and dialogue served up sharp and crisp.

Here's Spenser in action, from "Rachel Wallace": "I'm looking for one of your people. Young guy, twenty-five, twenty-six. Five ten, hundred eighty pounds, very cocky, wears military decorations on his uniform blouse. Probably eats raw wolverine for breakfast."

The taciturn detective was in top form, by turns accepting and arguing with the calming, psychoanalytic observations of his longtime love Susan Silverman (an idealized stand-in for Joan, Parker's wife of 52 years), as well as the violence-prone impulses of his partner, Hawk.

This tripartite emotional construction was hardly new in crime fiction, but Parker took it in unexpected directions as Spenser struggled to reconcile his domesticated, gourmet-cooking self with the instinctive brutality of a character such as Hawk.

Being imitated

As Spenser's adventures continued to appear at an annual clip, writers such as Robert Crais, Harlan Coben and Dennis Lehane refashioned Parker's hero-sidekick dynamic as they saw fit.

"When it comes to detective novels, 90 percent of us admit he's an influence, and the rest of us lie about it," Coben told the Atlantic in 2007. The numbers can be debated, but the sentiment is indisputable.

Coincidentally, Spenser's peak period ended roughly around the time he migrated to network television, first on the weekly series "Spenser: For Hire" (1985-1988), and later in four TV movies.

Though Parker carried on writing about the character, he turned increasingly toward new protagonists who drove long-running series of their own: the small-town police chief Jesse Stone, portrayed on television by Tom Selleck, or the female detective Sunny Randall, originally envisioned as a vehicle for Helen Hunt.

He also wrote a trilogy of novels about the Old West, the first of which, "Appaloosa," was turned into the 2008 film directed by Ed Harris.

By the end of his life, Parker was less known for his content than for his prolific output; he produced up to three published books a year.

"I normally write seven to 10 pages a day, which means I generally finish a new book every three months," he told the Wall Street Journal in 2009. "It comes easily, and I don't revise because I don't get better by writing a new draft."

As a consequence, even as he remained a fixture on bestseller lists, Parker's most ardent fans turned into his toughest critics, pointing to ever-increasing white space, decreasing word counts and long passages of dialogue that barely moved the action forward.

Reconnecting

Those very flaws, however, also suggest one of the charms of a long-running series: the chance to reconnect with beloved characters whose behavior fits an expected pattern, whose conversation taps deep into collective memory.

In that sense, spending time in Parker's company these last several years was akin to attending a concert by Frank Sinatra or Ella Fitzgerald late in their careers: There was just enough juice to revisit the standards, and it hardly mattered if the tone warbled into an echo of former melodious glory.

After all, like those vocal greats, Parker's legacy is as much about influence as it is about production, and his ability to drag the private eye into a new era, reframed by women's liberation and 1960s-era activism, counts just as much as any of the exploits in his books.

Weinman writes "Dark Passages," a monthly mystery and suspense column, for latimes.com/books. She blogs about the genre at Confessions of an Idiosyncratic Mind ( www.sarahweinman.com).