“Lakeboat” really doesn’t go anywhere, but Joe Mantegna’s filmization of David Mamet’s early play is still worth seeing. Though it’s been visually opened up by location shooting, the story about the camaraderie among a group of guys on a freighter making a summer sail on Lake Michigan from Chicago to Duluth is little more than a succession of acting exercises–monologues and conversations–and even off the boards it remains extremely stagy.

But who cares when the dialogue is so meaty and the performances so canny? The writing periodically bristles with Mamet’s typically machine-gun rhythms, and at other times subsides into a mood of nostalgic reverie. The mixture of repetitive, rat-a-tat riffs (often extremely funny) and more somber, elegiac moments (sometimes quite sad)–occasionally punctuated by pregnant pauses–is compelling in itself, but it’s made irresistible by what’s mostly a dream cast. Things start off marvelously with Peter Falk (as the gruff pierman) delivering a hilarious dockside speech about a crewman who’s absent as a result of a beating he received requiring hospitalization. (Imagined versions of this episode–featuring Andy Garcia as Guigliani, the injured man–reappear throughout the piece, told from the perspectives of different shipmates and becoming more and more exaggerated.) Then we’re treated to nearly-as-fine declamations by Charles Durning, as the ship’s captain, Skippy; George Wendt, as Collins, his second-in- command; Robert Forster, as Joe, a respected old hand with a perpetually hangdog expression; J.J. Johnston as Stan, a foul-mouthed, opinionated hard-ass; and Jack Wallace, as Fred, a rather dense fellow with a desire to please. (An argument between the last two over the machismo of Steven Seagal shows the play’s age, but is still hilarious. When heavyweights Durning and Wendt engage in their banter while sauntering about the deck or holed up on the bridge, the effect is genuinely endearing. And Forster’s sad-faced recitations about his past, as well as his salty dialogues with Johnson’s Stan, are simultaneously weighty and amusing.)

There are weaknesses in the cast. Denis Leary, as an engine-room worker with a taste for pornography, tries too hard to appear eccentric, and Tony Mamet, the writer’s younger brother, is pallid as Dale Katzman, the college boy temporarily replacing Guigliani as the night cook and cleaning man. (The piece is plotted as a coming-of-age story, in which Dale matures through his contact with the rough fellows on the ship and ultimately earns their respect. It’s typical Mamet territory, and a rickety construct at best.)

But these lapses are minor compared to the thespian feast on display. Mantegna, who’s performed a good deal of Mamet himself on both stage and screen, knows his way around the playwright’s characteristic material, and encourages his stellar performers to savor its richness without going overboard; even the most impassioned outbursts are held in check, and the stars never seem to be playing to the second balcony (as so often happens when plays are transposed to the screen). Mantegna also appears in a brief cameo in one of the Guigliani flashbacks, which grow progressively more absurdist as the narrative runs on, building to a jokey climax. The picture closes as the ship docks, young Dale ends his internship and returns to his studies, and Guigliani makes a sudden reappearance.

Given the fact that most of the action is confined to verbal sparring in a confined shipboard environment, “Lakeboat” looks fine–a testament to the expertise of cinematographer Paul Sarossy. The opening shots of the Chicago skyline, eventually coming to rest at Navy Pier, are quite lovely. But even they pale when the actors take center stage. Mamet’s play and Mantegna’s picture may be little more than a standard “Education of a Young Man” scenario, the sort of thing we’ve seen countless times before in war movies, westerns, and every other imaginable setting. But here it’s been transplanted to a new, unexpected locale and invigorated by sharp writing and masterful acting. The result may be relatively minor Mamet, but it provides major enjoyment: a crock, but a crock that’s fun to watch.