"City Heat" proves you really can have too much of a good thing. Pairing Clint Eastwood (Mr. Box Office) with Burt Reynolds (Mr. Box Office Jr.) as a Kansas City cop and his private-eye sidekick caught up in a war between rival Depression-era gangsters, the movie's never as good as it might have been.

Reynolds plays Mike Murphy, a "hole-in-the-shoe peeper" who left both the force and his partner Lt. Speer (Eastwood) to open his own detective agency; his new partner, Dehl Swift (the charismatic Richard Roundtree), becomes a bagman trying to double-cross two mob factions and ends up dead. Murphy slyly assumes Dehl's chores -- he's plotting revenge -- but he can't shake Speer, who follows him as stealthily as a rumor. "I didn't hear you knock," Murphy says; "What a relief -- I thought I'd gone deaf," Speer replies.

Penned by Sam O. Brown, "City Heat" swirls with smart-guy repartee between Reynolds and Eastwood and, after they team up, between them and their adversaries (played nicely by Tony Lo Bianco and the incomparable Rip Torn, still crazy after all these years). In a warehouse scene, Eastwood tells a group of palookas that he has 20 cops outside; when they check the street, though, it's only an old man and his dog. "That's Sergeant Lefkowitz," Eastwood says. "Who's the guy in the dog suit?" Reynolds deadpans.

Here, as elsewhere in the movie, such nudge-and-wink stuff is a prelude to mayhem. Director Richard Benjamin ("My Favorite Year") orchestrates the violence well, using a jiggly hand-held camera that becomes the target for a chorus of jabs and kicks that crash into the lens; and his jazzy crane shots become the perfect complement to the jazzy score. But Benjamin shoots identical scenes identically -- there isn't a single surprise in the movie. "City Heat" exemplifies the gulf between visual style and visual storytelling.

The same flaw sabotages Brown's flashy script, which begins with meticulously engineered complexity but degenerates into a junkyard of hit-or-miss skits showcasing the stars, who cancel each other out the way an explosion can extinguish a fire. With his pinkish, furrowed skin stretched back from his eyeballs, Eastwood now looks less like a gunslinger than the guy selling him the gun; as the noble prow of his coiffure has retreated to a beleaguered thatch, Eastwood has consciously eroded the feral perfection of the loner he once thrived on. In the best of his recent movies, he probes or gently satirizes his persona. But the attempts to humanize Eastwood, particularly his love interest with Murphy's secretary (Jane Alexander, who has never been dowdier), are just distracting here. And Eastwood doesn't do anything in "City Heat" that he didn't do more subtly in "Bronco Billy".

More to the point, with Eastwood playing off himself, there isn't anything left for Reynolds to play off -- the stars run parallel; they never connect. In becoming a celebrity, Reynolds has discarded any notions he had of acting; in recent performances, he just offers the hem of his skirt for his fans to kiss. Sashaying through the role, Reynolds plays against machismo, too -- but his old persona was so slight, it hardly seems worth the bother. Such merciless mugging is just a way to show off how much fun it is to Be Burt -- he might as well be clowning on "The Tonight Show." Thank heavens his buddy Dom DeLuise refuses to lose weight -- it would be impossible to tell them apart.

As these samurai cosh, ignite, bludgeon and blow away a host of contemptible nincompoops, "City Heat" can suggest "Yojimbo"; violence in this movie is mostly slapstick, but it can be shockingly, daringly cruel, too. Lamentably, such impulses are smothered by embarrassingly broad comedy and Benjamin's smarmy fealty toward his leads. Inside this star vehicle there's a real movie screaming for air. "City Heat," opening today at area theaters, is rated R for profanity, violence and mild sexual situations.