MOVIE REVIEW : ‘The Firm’: How to Build an Air-Tight Case : Sydney Pollack gives John Grisham’s novel an altered but polished treatment. Tom Cruise and Gene Hackman top an exceptional cast.

When a book sells 7 million copies and is translated into 29 languages, who can doubt that it is doing something right? So the inevitable film adaptation has to decide whether to play it perfectly safe or take risks with what is close to a sure thing.

The powers behind “The Firm” (citywide) have avoided the dilemma by splitting the difference. They have carefully protected the core qualities of the John Grisham novel while radically rejiggering its plot line. The result is a top-drawer melodrama, a polished example of commercial movie-making that manages to improve on the original while retaining its best-selling spirit.

Clearly, Paramount Pictures, which purchased the movie rights to this story of lawyers on both sides of the law even before it was sold as a novel, wanted the best for this project, and when Hollywood wants the best in mainstream directing, Sydney Pollack is always on the list.

Though “Havana,” his last film, was a misfire, Pollack remains the total professional, an actors’ director and one of the foremost practitioners of the kind of nicely calibrated work that is so smooth there is a danger of discounting the amount of skill that goes into it.

Casting was a similar gold standard production. As hotshot attorney Mitch McDeere, Tom Cruise, the heartthrob of the moment, was the obvious choice, and “The Firm” not only pairs him with Gene Hackman as legal mentor and Jeanne Tripplehorn as loving wife, but also fills in the background with the strongest and most varied group of supporting actors in memory.

“The Firm’s” most intriguing credit, however, is the one for screenplay, divided as it is between a trio of exceptional writers who are as accomplished as any mob hit men: playwright David Rabe (“Streamers,” “Sticks and Bones”), four-time Oscar nominee Robert Towne (“Chinatown,” “Shampoo”) and longtime Pollack collaborator David Rayfiel, who also worked on the director’s similarly themed “Three Days of the Condor.”

*

If “The Firm’s” intention was to simply replay the novel, this much talent wouldn’t be necessary. But what’s been done here is similar to rebuilding an engine: The book’s best-selling plot has been taken apart and put back together again in noticeably better shape. Subplots have been strengthened, characters switched around to make the jeopardy more emotionally involving, and increased physical action has been added to the mix, all of which ratchets the excitement level up a number of notches.

“The Firm’s” narrative focus, however, has been kept intact, and that involves the trials of lawyer McDeere. The film’s opening sections quickly establish him as a top prospect at Harvard law, a loophole-loving tax lawyer whose days of waiting on tables and riding the bus home to patient spouse Abby are soon to end in a welter of big-money proposals from fancy firms.

But the offer McDeere ends up being unable to resist comes not from New York or L.A. but rather courtesy of a small, 41-lawyer outfit in Memphis named Bendini, Lambert & Locke. Not only do they propose to pay top dollar, but they throw in a low-interest home loan and a new Mercedes, color to be determined later, as extra added incentives.

A visit to Memphis and lots of talk about how everybody in Bendini is one cheery family clinches things for McDeere. Though Abby is put off by the Stepford quality of some of the corporate wives and thinks maybe things are too good to be true, the ambitious Mitch, clearly too busy a young man to read many novels, is unworried by the surface perfection.

The first blemish on McDeere’s dream comes when two members of the firm die violent and unexpected deaths. Then he gets rousted by a pair of surly men who just might be government agents. Gradually, much against his will, McDeere comes to suspect that Bendini is not exactly the paradise it appears. But like Harry Houdini, bound in chains and tossed overboard, his situation is one from which escape seems impossible, and every move he makes only serves to tighten his bonds.

Though Mitch McDeere can never quite escape being more a cog in a thriller machine than a character, Tom Cruise goes a surprising distance toward making him believable. The actor’s charisma has never been in question, but under Pollack’s guidance his charm, though evident, has been so muted that when he’s called on to be awkward and in jeopardy it is convincing.

Also plausible is his relationship with wife Abby, as Cruise and actress Tripplehorn (Michael Douglas’ wretched girlfriend in “Basic Instinct”) make a much more charming romantic pair than Cruise and real-life companion Nicole Kidman did in “Far and Away.”

Even more impressive is the range and quality of performances “The Firm” (rated R for language and some violence) has gotten from its supporting players. Usually star-driven vehicles have one or two smaller roles that are worth commenting on, but here attention must be paid to more than half a dozen ensemble bits. Included are Gene Hackman’s major turn as McDeere’s troubled associate, Wilford Brimley as the firm’s ominous head of security, David Strathairn as McDeere’s brother, Gary Busey and Holly Hunter as private investigator and loving secretary, Ed Harris and Stephen Hill as government operatives, even fallen mogul Jerry Weintraub as the disreputable Sonny Capps and “Wide Sargasso Sea’s” Karina Lombard in the small but critical role of a young woman on the beach.

When so much of the acting in a film is quietly effective, an extra nod must be given to the director. Sydney Pollack has not only taken the risk of letting his film run the two and a half hours needed to include relevant characterization, he has demonstrated how emotional shading and subtlety can be worked into big-ticket items. Contrary to so much of what we’ve seen this summer, “The Firm” proves that a presold blockbuster doesn’t have to be the dumbest film on the block.

‘The Firm’

Tom Cruise: Mitch McDeere

Jeanne Tripplehorn: Abby McDeere

Gene Hackman: Avery Tolar

Hal Holbrook: Oliver Lambert

Terry Kinney: Lamar Quinn

A John Davis/Scott Rudin/Mirage production, released by Paramount Pictures. Director Sydney Pollack. Producers Scott Rudin, John Davis. Executive producers Michael Hausman, Lindsay Doran. Screenplay by David Rabe and Robert Towne & David Rayfiel, based on the book by John Grisham. Cinematographer John Seale. Editors William Steinkamp, Ferederic Steinkamp. Costumes Ruth Myers. Music David Grusin. Production design Richard MacDonald. Art director John Willettt. Set decorator Casey Hallenbeck. Running time: 2 hours, 33 minutes.

MPAA-rated R (language and some violence).