The Detective: Surveillance guru - "the best bugger on the West Coast" - who lets professional perfection get the better of him as he attempts to figure out the meaning behind The Conversation (1974).
Why They're Cool: While he's not a detective in the traditional manner, Gene Hackman's performance ensures that Caul is an archetypal 'tec - anal, obsessive and a devil for detail.
Quintessential Quote: The line on the taped conversation that gives Caul such grief - "he'd kill us if he got the chance."
The Detective: African-American psychologist-turned-Fed, created by James Patterson and played twice on screen by Morgan Freeman and, recently, Tyler Perry.
Why They're Cool: Not for the last time on this list, Freeman's gravitas underscores Cross' status as one of the deepest, most cerebral cops around. Judging by the critical reception for Cross (2012), Perry hasn't achieved the same.
Quintessential Quote: "I'm a forensic psychologist. It's a fancy way of saying I'm a guy who walks into a room like that and determines the hows and whys."
The Detective: Real-life San Francisco inspector notable for a) wearing his gun upside-down in his shoulder holster and b) failing to catch the eponymous killer in Zodiac (2007).
Why They're Cool: Mark Ruffalo nails the hip 1960s vibe, playing a celebrity cop so stylish Steve McQueen used him as the model for his role as Bullitt .
Quintessential Quote: "Easy, Dirty Harry."
The Detective: LAPD 'tec transferred to Alaska, who finds his anxiety over an Internal Affairs investigation merging with the perpetual Arctic light until he's suffering from Insomnia (2002).
Why They're Cool: Al Pacino reins in his propensity for bug-eyed shouting to make Dormer a shifty, heavy-lidded pile of nerves.
Quintessential Quote: "Let me sleep."
The Detective: Classic 1930s comic-strip mob-hunter who got his very own primary-coloured blockbuster in 1990 courtesy of star/director Warren Beatty.
Why They're Cool: In theory, Tracy is a dull, lantern-jawed hero unblemished by complexity or charisma. But he sure knows how to wear a raincoat and fedora.
Quintessential Quote: "You're one in a million."
The Detective: LAPD narc seen in Training Day (2001), whose street-smarts allow him to run a sideline in extortion - but when everybody on the force is corrupt, who's gonna notice one more rogue cop?
Why They're Cool: Denzel Washington achieved the rare feat of winning Best Actor for playing a bad guy by making Alonzo a suave, charismatic villain compared to uptight 'hero' Ethan Hawke.
Quintessential Quote: "My nigga."
The Detective: Two-bit private detective whose business struggles because of Valiant's pathological hatred of toons, who has to get over his prejudices to discover Who Framed Roger Rabbit? (1988).
Why They're Cool: Bob Hoskins knows that he's second fiddle to the animation and underplays accordingly - creating a plausible, messily human centre amidst the mayhem.
Quintessential Quote: "Get this straight, meatball. I don't work for toons."
The Detective: Corrupt, venal private eye played by M. Emmet Walsh in Blood Simple (1984), who spots an opportunity to double-cross his latest client.
Why They're Cool: The antithesis of the usual 'white knight' movie detectives, Visser is a disgusting slob with a malicious cackle.
Quintessential Quote: "Gimme a call whenever you wanna cut off my head. I can always crawl around without it."
The Detective: Apparently brilliant, but obviously not, member of Police Squad who somehow remains blithely unaware of the chaos he causes in The Naked Gun (1988) and its sequels.
Why They're Cool: With Leslie Nielsen reuniting with Airplane! co-director David Zucker, Drebin's buffoonery nails every detective movie cliché to the wall.
Quintessential Quote: "Wilma, I promise you; whatever scum did this, not one man on this force will rest one minute until he's behind bars. Now, let's grab a bite to eat."
The Detective: High school student who has to play sleuth in Brick (2005) when his ex-girlfriend is murdered.
Why They're Cool: Joseph Gordon-Levitt helped to shake off the millstone of Third Rock From The Sun with his canny, knowing blend of detective movie nous with teenage angst.
Quintessential Quote: "Ah, the folly of youth."