The missing word-pair from the title is "riff riff," because Shane Black's comic actioner can't stop referencing, homaging and tweaking other works of popular culture. Not that there's necessarily anything wrong with that. Kiss Kiss, Bang Bang is an entertaining romp through a certain subset of late-20th-century junk culture, and the more you already know about pulp-detective fiction, crime films and Hollyweird, the more fun you'll have.
Our guide on this ride is Harry Lockhart (Robert Downey Jr.), a petty thief in New York City who eludes the law one night by barging onto a film set. His realistic portrayal of a stressed-out criminal wows the director, who mistakes him for an actor, and it nets Harry a trip to Los Angeles for a screen test. To prepare for his potential role as a detective, Harry tags along with Perry van Shrike, a.k.a. Gay Perry (Val Kilmer), a cool, sharp-tongued real-life dick.
But the twisty hi-jinks have just begun: Harry also hooks up with Harmony (Michelle Monaghan), his long-lost high school sweetheart who just happens to be at the same party. And before you can say "Raymond Chandler sent me," there's a little sister, a dead body, a couple hit men, a loony bin, a stolen car, a missing finger, and so on. It's like they're all living in a Jonny Gossamer pulp: Gossamer, you'll learn, wrote such tough-guy bus-station classics as You'll Never Die in This Town Again and Small Town Boy Makes Dead, and has been adopted as a mentor by several of this film's characters.
Kiss Kiss was written for the screen by Black, but is partly based on the late-'50s Brett Halliday pulper Bodies Are Where You Find Them (that's a real book, not a joke title). While Black makes his directorial debut here, he's no stranger to the scene, having penned several successful action comedies (he lays claim to no less a feat than inventing the buddy-action flick with his script for Lethal Weapon). Thus he has as much fun jabbing at Hollywood (including a nod at Downey's infamous drugged-up house-breaking incident of a few years back) and the glossy, dead-eyed milieu of desperate, brittle wannabe stars, as he does with the conventions of the action genre and detective pulps.
So Black effectively combines the looseness of the buddy flick with its quips, vulgar pratfalls and shaggy characters (Downey, the consummate Hollywood insider, plays the befuddled outsider with much goofy charm) with the ludicrous, convoluted plot of a hardboiled pulp novel. The details of the story are moot: It's the journey that matters, as the wry cynical hero trolls through alleys, gin joints, bad dames and worse liquor on a quest for justice and order in an upside-down world -- while also making us laugh. 
