Sure, there are other characters in the sophomore season of HBO's True Detective, but it's the battle between Detective Ray Velcoro (Colin Farrell) and his moustache that offers the most gut-wrenching relationship.
In flashback, clean-shaven cop Velcoro enters a Faustian bargain with mobster Frank Semyon (Vince Vaughn). Fast-forward a few years and Velcoro's now Captain Burnout, cursed with the modern fictional detective's scarlet letter: a moustache.
That crumb catcher compels Velcoro to utter bon mots like "12 years old? Fuck you," to a schoolyard bully after beating his father half to death. Hell, when Velcoro passes out after drinking a bottle of whisky, his moustache probably separates from his body and continues the cruising, boozing and fighting.
Velcoro's moustache epitomises fatalism. In hock to the swinging dicks of municipal corruption, his snot mop - and to an extent his power - can be shorn off at a moment's notice should the odious public officials and underworld hoodlums conspire to buy Velcoro shaving cream and a razor.
Farrell has form with fictional detective lip foliage. In Miami Vice, Michael Mann's bromance-cum-installation-art piece, he deployed the face fur to suggest a detachment from the modern world that cannot be conveyed with mere words. The misery of taking your hot mob girlfriend to Cuba for cocktails in a speed boat can only be emoted with facial hair last seen adorning a heavy metal bass player on their band's failing comeback tour of Japan.
True Detective's creator Nic Pizzolatto (or, as the Los Angeles Review of Books lovingly calls Pizzolatto, 'The Pitz') first realised the tragedy of the moustache in the show's freshman season. Det. Rust Cohle (Matthew McConaughey) went from crazed loner detective to crazed loner drunk when he put the Gillette Mach 3 to the side - quitting the force, and switching milk for special brew on his morning Frosties to "maintain".
Cohle's mumbo jumbo was now filtered through a Harley Davidson death cult lipholstery that drooped all the way to washed-up cop hell. Over in the UK, Red Riding saw Maurice Jobson (David Morrissey) plot, cover-up and cajole from behind a moustache grimmer than the northern sky he conspired under.
This wasn't always so. Back in the 50s, Charlton Heston grew a pencil-thin line across his upper lip to pass as upstanding Mexican cop Mike Vargas in Touch of Evil. While in the 70s, the detective tache reigned supreme in Shaft with Richard Roundtree's proto-baller face rug.
The 80s saw the mustachio detective became a symbol of the family man, proudly growing on Roger Murthagh's (Danny Glover) face in Lethal Weapon. Tacitly his flavour saver said 'No' to crime in a way partner Martin Riggs's (Mel Gibson) Aussie mania never could. Murthagh's moustache was neither happy nor sad. It was simply a rock of justice.
Yet as attitudes changed, so to the grass grin came to be viewed with the same mistrust as that other hallowed signifier of lost masculinity: cologne. Picked knowingly from a Playboy article called '10 Scents That Will Drive Women Wild', cologne wasn't just the name of a German city but something tache-tastic lady killers like Magnum PI drenched themselves in. Now it is more likely to be worn by an actual lady-killer.
Perhaps Velcoro has moved on from cologne by instead dousing himself in the modern equivalent: deodorant - hiding his sins from a watchful, ever vengeful and never cool deity.
Books still provide the moustached and righteous fictional detective with a final, secretive holdout. Michael Connelly's absurdly serious Harry Bosch sports one, James Ellroy's racist Det. Sgt. Lloyd Hopkins recites murder beefs to his daughter from behind his, and Kinky Friedman twiddles his whiskers while listening to singing canneries and country ballads. Perhaps on the morning commute the reader gets off dreaming of exacting full-on tache justice on the scum of society sitting opposite who just won't turn down their iPods.
Alas - in the world of television and film - short of tattooing 'Tool' on an actor's forehead, the moustache seems here to stay as the preferred shorthand for the emotionally conflicted detective.