JOHN GRISHAM’S ninth novel, The Street Lawyer, follows the basic formula of his other bestsellers, taking a jaded lawyer disillusioned with the American system of justice and–through a series of dire and not always believable events–leading him back to his original idealism through the true promise of those same institutions.

The book opens like so many Hollywood movies, with a bravura setpiece. Michael Brock, Grisham’s first person narrator, arrives at his swanky Washington, D.C., firm’s office for work one morning, tailed by a ragged homeless man. Like any resident of our nation’s capital, Michael is used to the homeless. They’re a nuisance, a daily pain the rich can afford to ignore. Almost bored with the situation, Michael asks for security to take care of the man.

Before that can happen, the man produces a gun and herds the high-priced lawyers into a room. Michael narrates the action, his jurist’s eye sharp when picking up other’s shortcomings and his own. The gunman, who tells them to call him simply Mister, asks them embarrassing questions like how much money they make versus how much they donate to the homeless. The results are damning, Michael agrees.

The police surround the place, snipers on rooftops, and after Mister asks, just once, enigmatically, who ordered the eviction, he makes a wrong move, giving the police a clear line of sight, and a sharpshooter splatters Mister’s brains all over Michael’s expensive suit.

The incident changes Michael, though from the beginning he seems to side with Mister against his fatuous colleagues during the siege. His marriage is already on the rocks. He spends too much time at the practice, and his wife Claire is well into her residency, too busy for him anyway. The hostage drama forces him to see his life as empty. Something has to change.

Puzzled as to why Mister decided to do what he did, Michael turns detective and investigates his captor. Unfortunately, Grisham gives us the terrible cliche of the homeless Vietnam veteran, hounded by drug and alcohol problems. It’s a stock character, and unfair, but it does the job. In tracking down the man’s connections, Michael stumbles upon a free legal clinic in a part of town where he’s afraid to park his Lexus. Suddenly his whiteness and wealth are noticeable in the same way Mister’s blackness and poverty were at the firm.

Michael meets the clinic’s guiding light, Mordecai Green–again, a standard type: half preacher figure, half savvy mensch. Green explains the details of the eviction. Some slumlord had divided a warehouse into cheap apartments, then thrown his mostly homeless tenants out when he saw a lucrative (and speedy) real estate deal. Michael’s firm was associated with this person and his business associates. They’d all made–so to speak–a killing.

Michael, looking for something good to do with his now empty hours (because of the shock of the event, the firm has given him sick leave), he volunteers at the clinic and begins to learn about the lives and problems of the homeless.

Much of this is done in dialogue, Michael avidly questioning and Mordecai providing answers. Grisham has done his research, and some of it–especially his gloss on homeless advocate Mitch Snyder’s CCNV–is fascinating, but no matter how integral to the plot, it still comes off as undigested research. And a fair amount of it is common knowledge; the homeless problem in America was widely publicized during the ’80s and early ’90s, a cause celebre featured in bad pop song videos. Not that the problem has gone away, but its trappings are old hat.

Michael soon comes to see his work with the homeless as the most valuable–maybe the only valuable–part of his life. He also comes to suspect his firm’s involvement in the eviction was not only immoral and unethical but illegal. (The rich screwing the poor for real estate this way is an old populist trope; in cheesy westerns it’s the bank helping the mean railroad take the plucky widow’s ranch, or, in the Blues Brothers, the orphanage. In real life, of course, it’s perfectly legal, but that would leave us with no plot.) He uncovers a file he believes holds the necessary evidence to prove this and–in classic Grisham fashion–steals it.

The act makes him an outlaw, a marked man. To complicate matters, as he’s fleeing with the file, Michael has a car accident. He’s struck by a drug dealer’s Jaguar and ends up in the hospital, his beloved Lexus with the hot file in it locked away in an impound yard. At this point he hasn’t even read the file; he just knows he’ll have hell to pay if the firm finds him with it.

Exactly why Michael doesn’t photocopy the file’s contents may be the plot’s greatest mystery. At worst it would take him a few nervous seconds in the office. Instead, Grisham pads out this unnecessary complication for several chapters. It’s an artificial plot point that undermines the novel as well as our regard for Michael.

The missing file with possibly explosive contents is a creaky device, but in recent years Grisham has breathed new life into it. That he resorts to it again only to mishandle it is disappointing. A pro, you think, should know better.

But the plot is rolling on, and there’s no time to split literary hairs. The firm sends the D.C. cops after Michael and the clinic, trying to discredit him and retrieve the damning information. Will Michael bring the truth to light? Will the homeless receive justice? Will the prodigal give his firm its comeuppance?

The answers are less important than Grisham’s vision of Michael as a man who has found, after wasting so much time on material values, something worth living and fighting for. The spiritual quest for a self connected to the best in humanity–as in The Partner, or his new American release, The Testament–is the true spine of the book. Grisham’s men discover within the law itself the possibilities of right and moral action and use it against those who have corrupted it. It’s no coincidence that The Street Lawyer, which turns on money, race and power, is set in Washington, D.C.

That is not to say the novel is introspective. Michael has little inner life beyond his musings on the plot, the law and the homeless. His marriage to Claire disintegrates in thumbnail summaries and a few brief, rather empty scenes. Conveniently offstage most of the book, she never becomes even a supporting character, just a prop. The drug dealer whose Jaguar hits Michael’s Lexus is killed, yet draws no thought from him whatsoever; twenty pages later our hero is driving again with no ill effects. Near the end there’s a last-ditch attempt at some budding romance with another do-gooder named Megan, but it’s thin, an afterthought not to be taken seriously.

Neither is the book truly heavy on plot. The storyline, for all its juicy possibilities, is simple, missing the twists and reversals of a whodunit or a thriller such as The Partner. In The Street Lawyer, the question is not who is guilty or whether someone is guilty but how to prove it. Michael’s suspicions are true on all counts. Nothing pops up and surprises us–besides, perhaps, the car crash, which proves to be a device.

Likewise, the moral of the story is too clear-cut to draw any complicated response from the reader. The big rich firm is mean and greedy and the homeless and their advocates saintly and put-upon.

It’s all right. To Grisham’s credit, reading the book takes so little thought and such little effort that the pages fly by. From the beginning of his career, his books have had that magical quality all pop novels aspire to–a combination of velocity and satisfying action that editors call readability. He has it here again, and he’s also managed a difficult feat, writing an incredibly light book on a heavy subject. That we might actually learn something in the process is a bonus.