Robert Downey Jr. (search) and Val Kilmer have turned gumshoe with "Kiss Kiss, Bang Bang," a murder mystery that could have been called "Nudge Nudge, Wink Wink" for its relentless yet loving tweaks at Hollywood film-noir conventions.

The film, which debuted Saturday at the Cannes Film Festival (search), both mocks and embraces the cliches of the hard-boiled private eyes of years past — taking to nearly outlandish levels the genre's improbable coincidences, impossible action and detectives who take endless lickings yet keep on ticking.

"This is a drunk movie," "Kiss Kiss, Bang Bang" (search) writer-director Shane Black told The Associated Press. "This is just a movie that had too many."

Downey stars as petty crook Harry Lockhart who, through bizarre chance, stumbles into a casting call and is flown to Hollywood to audition for a cop movie. To prepare for the audition and lend authenticity to his performance, Harry is teamed with private detective Perry van Shrike (Kilmer), known as Gay Perry for his sexual preference.

During a supposedly harmless stakeout, Harry and Perry end up the keepers of the body of a beautiful dead woman that keeps coming back to haunt them.

At the same time, Harry has an unlikely reunion with Harmony Faith Lane (Michelle Monaghan), his dream girl from high school, a wannabe actress in need of a private eye to look into the suspicious suicide of her sister.

Figuring that playing the hero could win Harmony's heart, Harry pretends he and Perry are partners and takes on her case, blundering into a tangled mystery that wittily plays with the car chases, tenuous clues and high body counts of classic detective stories.

"Growing up, I loved those fast-talking, loose-jointed, shambling-rhythm, chain-smoking, womanizing kind of guys," said Black, a screenwriting prodigy in his early 20s with "Lethal Weapon," now making his directing debut. "On the other side, I love very disturbing, psychological, edgy stories. I wanted to do it all.

"To put it all in a movie, already you're sort of stacking your movie. So I thought, let's just throw in the kitchen sink. Let's start standing some cliches on their head. If I'm going to make a bizarre little movie, let's make it really bizarre."

Black was especially influenced by mystery writer Raymond Chandler, whose story titles the filmmaker borrows as chapter headings for "Kiss Kiss, Bang Bang," which opens in U.S. theaters this fall.

Throughout the film, Harry not only narrates the action, but also denigrates it at times, commenting on improbable plot twists and groaning over moments of outlandish action.

"It's a movie that knows it's a movie," said Joel Silver, producer of "Kiss Kiss, Bang Bang," who also made the "Lethal Weapon" movies.

"Kiss Kiss, Bang Bang" presents a sly parody of the ubiquitous buddy-cop flicks Black helped usher in with "Lethal Weapon." It also gives viewers the action they've come to expect in those movies along with a house-of-cards puzzle with enough blind alleys to tease the most avid mystery fan.

"It's that regard for anyone's intellectual ability to assimilate something and figure it out and work with it," Downey said. "That's what makes it so different."