If all you're seeking for your summer reading is a good mystery with a fast pace and suspense that lasts, you could do far worse than "Bad Boy Brawly Brown," the 12th book and seventh Easy Rawlins story from Walter Mosley.

But just as there's a lot more to Mosley than Easy Rawlins, there's a lot more to the Easy Rawlins series than good guys and bad.

One of the wonders of Mosley is that he so consistently and successfully blends plot and character with substantial social commentary.

If this is Easy, this must be LA, and it is, though Mosley, who brings Easy back for the first time in a half-dozen years, finds him this time in the mid-'60s, after JFK but before the riots. Black militants have begun their rise, and the title character has enlisted.

Just what Brawly Brown is up to remains in doubt throughout the book. Easy has been asked to find out, and perhaps to bring him home, by Brawly's mother and her boyfriend, John, a close friend of Easy's.

Although Easy is settling down - he leads the large custodial staff at Sojourner Truth Junior High and has formed a family of two orphans and a loving partner - he still thrives on the buzz that has coursed through his life as a trader in the "economy of favors." So he agrees to take on the task in exchange for dinner between the families.

Brawly, who's in his early 20s, has been buffeted throughout his life. His father walked both sides of the law, and his mother suffered a breakdown after a crime went bad. The cousin who takes him in takes advantage of the young teen, adding abuse to the insults of Brawly's life. By the time the militants come along, Brawly is ripe for recruiting.

In the book they're not the Black Panthers but the First Men.

Though Easy is a thinking and sympathetic man, even more so than in the past, the first time he regards them he calls them thugs. It's an attitude and expectation shared by many older black characters who've made their way in the world by working around white dominance, rather than seeking to overthrow it.

Reprising their familiar role in fiction as storm troopers, the Los Angeles police are hellbent on stopping the Men, even if it means working multiple avenues outside the law to do it. The Men want to educate the young, feed the needy, and foster community, but at least some of them are willing to shed blood to achieve their aims, and that's all outsiders can hear.

The violence, or its threat, fits right into Easy's life. His best friend, Mouse, whose recent death haunts Easy from the book's first sentence, was as vicious as a man can be. Two men are murdered as "Brawly Brown" unfolds, and mayhem ensues.

More than once, violence is Easy's salvation, an example of the complexity wrought by Mosley; even as Easy is striding the mean streets, for example, his home is a cocoon of love. LA may be a stark world of blacks and whites, but most experiences come in shades of gray.

Mosley is fond, of course, of painting scenes in Technicolor. His fans know that the Rawlins stories come with a color in the name, and he doesn't stop with the title.

In "Brawly Brown," he emphasizes the individuality within the black community by mentioning skin tone in his descriptions: "medium brown leather," "ochre-colored," "eggshell brown," "cork-colored," "golden brown," "light brown," "muddy brown," and just plain "black enough as it is," as John describes himself as he laments his outside job.

One of Mosley's finest feats as a writer is that you can depend on his ability to entertain; no matter his subject, you can expect that the words will fit together snugly. At the end of a conversation with his daughter, for example, Easy remarks: "She hung up and I felt loss that went all the way back to my childhood." And at the end of a dream visitation by Mouse, Easy says, "The anguish I felt was like a grease burn; it started out painful enough, but then it dug deep."

The flaws in "Brawly Brown" are few: The language becomes slightly polemic once or twice, and a couple of turns seem a bit too convenient, but they're superficial, as much the product of reviewer's scrutiny as of anything important.

The fact is, Mosley has done again what many writers wish they could: Invest fine writing in complex characters, give them a believable plot that's set on a real, recognizable landscape, and make it seem as effortless as an easy day in the sun.