It is well suited to the the Noir canon – we see the usual suspects: damsel in distress sauntering into our hero’s office – unfolding into blackmailers, dirty doctors, mobsters, gritty cops and yes: more dames. The 1969 adaption of Little Sister, “Marlowe” starred James garner and led to the long running Rockford files.
It’s got all the elements of a hardboiled detective novel, emphasis on detective: that fedora topped character, with all flaws and humanity about him, is what draws us in rather than cunning plot lines. Generally Marlowe stands out among hardboiled and well heeled mysteries alike for several reasons: he doesn’t nab the criminal, does not explain the motive, merely observing and perhaps with subtle manipulation, opens a channel for a balancing of the scales. He never catches nor prevents, moving within a case as a riddle solving voyeur.