Will Eisner, 87, the comic book and graphic novel legend who died Jan. 3 in Fort Lauderdale, Fla., after quadruple heart bypass surgery, spent many years drawing scenes of standard heroics for an audience he imaged as "15-year-old cretins from Kansas."

Freed from convention in 1940 with an expanded comics section in newspapers, he broke with the form and revolutionized comics with "The Spirit" in the 1940s -- "sequential art," he called it -- and later by writing one of the earliest graphic novels.

With "The Spirit," he said his target audience was "a 55-year-old who had his wallet stolen on the subway. You can't talk about heartbreak to a kid."

"The Spirit," a syndicated strip seen by millions between 1940 and 1952, was Mr. Eisner's most famous early creation. It featured a crime fighter named Denny Colt reborn as a protector of public good and, especially, pretty girls.

Colt was a superhero without superpowers -- a radical nuance that met with popular acclaim and signaled the ambitious motif that defined his career.

His later works were reviewed by the New York Review of Books, which once noted that with Mr. Eisner, "the comics medium becomes something naturalistic, wry, introspective, and literate -- that is, in the comics universe, something truly otherworldly."

With his publication in 1978 of the graphic-story collection "A Contract With God and Other Tenement Stories," Mr. Eisner paved the way for such works by Art Spiegelman and Michael Chabon.

He created dozens of books with themes serious and frivolous. One of the comic industry's highest honors, the Eisner Award, is named for him.

"I've been trying to prove what the medium can do my whole life," he once said. "If I thought my point had been made, I don't know what I'd do."

William Erwin Eisner was born March 6, 1917, in Brooklyn, N.Y., to Jewish immigrants. He knew intimately tenement life that would act as backdrops for his art. Silent films, pulp magazines and the books of O. Henry provided his escape and enjoyment from a rough upbringing.

He attended De Witt Clinton High School in the Bronx, where his peers included "Batman" co-creator Bob Kane. He started his first comic strip in high school and at 18 became an advertisement illustrator for a New York newspaper.

Freelance comic assignments followed, and he befriended a magazine editor, "Jerry" Iger, with whom Mr. Eisner partnered in a venture to sell their own comic drawings to publications.

Recruiting Kane and others, he and Iger helped create Mort Meskin's "Sheena" and Lou Fine's "Dollman." Mr. Eisner drew "Hawks of the Seas," a high-seas adventure strip.

In 1939, Mr. Eisner left the business to accept an offer by the Quality Comics Group to be part of a massive and novel effort to produce an insert newspaper supplement built around comics.

Mr. Eisner had to overcome the objections of syndicate officials who could not fathom Denny Colt, the suit-wearing detective who protects Central City, as a viable competitor to caped crusaders like Superman and Batman.

Mr. Eisner was said to compromise by also giving Colt a blue mask and gloves, although he later complained that the mask "got in my way over the years, it didn't help the story, and interfered with what I considered the reality."

"The Spirit" also featured Ebony, one of the first recurring black characters in a mainstream cartoon.

Almost immediately, the strip explored psychological terrain and social commentary seldom before seen in the comic world. One story line compared convicts behind bars and a man unhappy with his sour marriage. The author also featured himself as a character, a post-modern twist, and still another strip was told from a killer's perspective.

Jules Feiffer, an admirer who once assisted Mr. Eisner on the strip, wrote in "The Great Comic Book Heroes" that "Eisner's world seemed more real than the world of other comic book men because it looked that much more like a movie. . . . The further films dug into the black fantasies of a depression generation, the more they were labeled realism. Eisner retooled this mythic realism to his own uses."

Mr. Eisner was drafted into the Army during World War II and left the strip in other hands. Recruited to draw cartoons, his "Joe Dope" series was used to show soldiers how to maintain their equipment -- and in a language they appreciated.

"Instead of 'Remove the residue from the vehicle,' we'd write 'Get the crud off your jeep,' " Mr. Eisner said.

After the war, Mr. Eisner tried to sell such ideas as "Nubbin the Shoeshine Boy" and "John Law," but they floundered. "The Spirit" ended, he said, in the wake of competition from television.

So in 1952, Mr. Eisner turned to the lucrative field of government training manuals, filling them with cartoons. He was extremely successful, working for the Defense and Education departments, and was outspoken in his belief that cartoons were an ideal teaching tool. He resurrected Joe Dope for many of his manuals.

When he rubbed against criticism that cartoon language often violated grammar standards, he countered that such a critique was "based on the assumption that cartoons are designed primarily to teach language. Comics are a message in themselves!"

Inspired by the underground comic work of R. Crumb, who revitalized the industry with vivid talk about sex and drugs, Mr. Eisner began to work in the 1970s on the book that became "A Contract With God." With their Depression-era Bronx setting, the minimalist black-and-white illustrations were filled with death, sadness and mature sexual themes.

"I'm dealing with the human condition, and I'm dealing with life," he told an interviewer. "For me, the enemy is life, and people's struggle to prevail is essentially the theme that runs through all my books."

He wrote several technical books about his craft, including "Comics & Sequential Art" (1985), and continued working through recent years. His stories often thematically addressed Jewish themes. "Fagin the Jew" (2003) re-imagined Charles Dickens's Oliver Twist from the dastardly villain's perspective.

He was a rousing presence at comic conventions and found spikes in popularity with new additions of his old "Spirit" strips. Original illustrations from "The Spirit" sell for $1,000 to $5,000, according to a published report.

A daughter died in 1969.

Survivors include his wife, Ann Weingarten Eisner, and a son.

Will Eisner created the "Joe Dope" character for the military and one of the earliest graphic novels.