Good vs Evil dualism and eternal conflict between the two.A detective story is a story about the "good" detective in a struggle against the "evil" criminal mind.
Except in Heat/L.A. Takedown where the point was that good people and evil people are the same. Maybe that is why it was crap.
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Moon Girl Technologies horrendous beanbag, Tue 12 May 2009, 16:11,
archived)
Another point might be that in contrast to other hero-based stories,the detective doesn't save the world or significantly change things for the better. He simply solves one case, and we presume that after the story is over, he goes on to solve more cases, and on in a neverending struggle. But he persists, because he's "good" and that's what being good means. Ultimately, he's only preserving a balance or status quo between the one side and the other.
Perhaps the point that Heat makes is that the difference between the two is entirely a case of taking sides, and that even though both sides are necessary to create a balance, the roles could nevertheless be completely reversed without making a jot of difference.
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Moon Girl Technologies horrendous beanbag, Tue 12 May 2009, 16:21,
archived)
Oooh. Yes. Very interesting. Thanks.(
LimeyTreat Bitch. Lover. Child. Mother. Sinner. Saint., Tue 12 May 2009, 16:25,
archived)