There's surely great pleasure to be taken in watching William Shatner play himself. And for about four minutes, Showtime makes the most of the opportunity. Shatner plays himself playing an expert adviser for the film's titular cop-buddy-reality TV series, which stars two "real" L.A. cops, grumpy twenty-eight-year veteran Mitch (Robert De Niro) and dilettantish showboat Trey (Eddie Murphy), who wants more than anything else to be a movie star.

As Shatner looks on with increasing frustration, Mitch goes up on his one line again and again. Meanwhile, Trey takes to heart every one of Shatner's pointers on, say, how to slide off a car hood with élan and how to arch an eyebrow for maximum TJ-Hooker effect. Being such an accomplished self-parodist -- from his Saturday-Night-Live minute ("Get a life!") to his more recent Priceline.com ads -- Shatner plays these scenes to maximum Shatner effect, remarking of Mitch, in overstated-aside fashion, "I've never seen such a terrible actor in my life!" Ha ha ha.

It's one thing for Bill Shatner to play himself. It's quite another for an entire movie to play him. The trouble with Showtime is that it never lets up on its self-congratulatory wink-winking. This isn't to say De Niro and Murphy can't do nifty and amusing self-parody (see Meet the Parents and Bowfinger), here, all the jokes are obvious and underwhelming. By the time Trey is charging toward the camera for his umpteenth close-up, you're really quite ready for the whole thing to be done with. And that's only about twenty minutes in. 

So, okay. Tom (Shanghai Noon) Dey's movie is not about anything than what it is: a collision of buddy cops with reality TV, peppered with shenanigans. Both genres, so formulaic, overdetermined by clichés and stereotypes, are eminently accessible for parody. That the parody is also a formula only doubles the fun. And so, you might wonder, what's the point? Ahh, but there you would be wrong. There's no wondering in formula. That's what makes it formula.

The gears get grinding like so: Mitch begins as a "real" cop, undercover to bust a "real" dealer (Mos Def, in a depressing part, in fact, exactly the kind of part that his character vehemently protested in Spike Lee's Bamboozled). (All the character types and concepts here should appear in scare-quotes to denote the hilarious irony they mean to represent, but wouldn't that be tedious to read?) The bust goes wrong when rookie uniform Trey mistakes Mitch for an actual criminal and calls for back-up; the TV van is listening in, and when it arrives on the scene, chaos erupts (in case you miss the essential premise here, the fight with Mos Def results in the shooting up of hundreds of hot TVs which he has stored in his "back room"). Mitch shoots one guy's shoulder-mounted camera, he's in trouble; the assault is, of course, broadcast, TV being the bane of all "real" people's existence here. Soon after, he's commanded by his desk-bound captain stereotype (Frankie Faison) to participate in this reality show, conceived and produced by Chase Renzi (Rene Russo, who mostly just looks tired).

She secures Mitch's participation, asserting that he's perfect because "women love bad boys." He, in turn, thinks the series has been conceived by "some Hollywood dickhead." And eventually, they -- surprise surprise -- couple up, thus fulfilling the primary buddy-movie necessity, that at least one buddy is visibly heterosexual. When Chase decides that Mitch needs a partner, a "funny minority type," Trey gets wind of the casting call. He arranges with his acting buddy (Kadeem Hardison, and what has happened to his career?) to demonstrate his abilities: the buddy plays Incompetent Mugger, Trey plays Self-Dazzling Hero, Chase plays Thrilled Producer, with Groveling Assistant in Tow. The rest of the film is like that, an ongoing car wreck of odious artifice that is, apparently, its own point.

In order to ensure that her fakey-fake show is a big reality hit, Chase takes it upon herself to rearrange the real cops' lives as much as possible (because it's just so funny to see Mitch fume and Trey prance about): she redesigns the police station so it looks like Men In Black's HQ, and provides new cars (Humvee and Corvette), so the "characters" conform to research on viewers' expectations of their buddy cops. Trey conforms enthusiastically, a "natural" pop star, coming up with catchphrases ("It's... showtime!"), renaming himself ("Ice Trey"), and puffing up his chest and looming for the low angle camera.

And oh, stop me if you've heard this before: when Chase insists that each guy spend five minutes a day in front of the "confessional" camera "Turn on your heart light!"), the movie's comedic montage sequence kicks in: Mitch announces, "I wish I was dead," then proceeds to eat bananas, read the paper, shaves, or, most cunningly, stare blankly at the camera; Trey spends his confessional time wondering aloud if he might do better with the "younger demographic" if he were partnered with a "Wesley Snipes type," rather than ancient, crotchety Mitch.

To complete the formula unto parody (even though the formula is rather parody by definition), Trey and Mitch are also on a "real" case while shooting the series. They're tracking a fiendish Latino villain named Vargas (Pedro Damián), complete with bleached blond tips and that familiar movie-gangster swagger (and stereotypically thick accent, and jeez, the film is so clever, it parodies that too). In between hanging out at Club Cuba Loco and murdering his employees, Vargas is buying up a load of handheld weapons that can shoot through trucks, body armor, and buildings. So, along with your parody and your formula, you get your explosions, vehicular and structural.

Showtime makes its colossal lack of originality its oh-so-po-mo point. But that's not so clever as it might have sounded to someone, somewhere along the line. Written by Keith Sharon, Alfred Gough, and Miles Millar, and based on a story by Jorge Saralegui (they would be the "too many cooks" of whom you've heard tell), and made for the ungodly sum of $90 million, it's a whole lot of too-muchness. Especially excessive are those "funny minority types," really just too familiar, as offenses and/or jokes, to be very funny.