Inherent Vice: Robert Altman, Thomas Pynchon, the Coen Brothers, and the Evolution of Stoner Noir.

In
basic terms, stoner noir is exactly what it says on the tin: a detective story,
drawing on the conventions of the Chandler/Hammett hard-boiled school, where
the protagonist happens to be a pothead.
This crucial interpolation is the main wheeze or ironic pivot around
which the genre is built.  Traditionally,
the detective has a certain gravitas, an inherent capability, about him.  The
hardboiled detective, as the name suggests, requires at least a modicum of
toughness; otherwise, going down the mean
streets on a routine basis would be life-threatening to an unhelpful
degree.  He needs to be able enough in
the realm of verbal and physical drubbing; quick to scoop up a pistol, and put
the drop on somebody, until the next party saddles in unexpectedly, and puts
the drop on him.   He needs to be able to
recover rapidly from the blow of a stiff blackjack on a cold night.  He’s normally cool, laconic, and
disciplined.  He has a certain sex
appeal, even if it’s that weird, rake-thin
longshore man with a mouth on him vibe that was only ever considered sexy
when manifested in the persona of Humphrey Bogart.  The hardboiled detective may, in a sense, be
a loser, but only in a noble or tragic manner; in a melancholic rather than
farcical register.