The only question that "So Dark thee Night" asks is: does the ending have a point or is it no more than a trick? I think it's both. But, nevertheless, one can say that the mature, astute detective's romantic obsession with the innkeeper's daughter does indeed shape the deep psychological turn which determines the shock ending.
But Lewis' direction of part one seems to weaken this scenario because by showing the detective's response to the young woman as light, carefree, insignificant, and as no one's business, the effect of his falling for her seems diminished. And yet there are signs of near psychosis in this breezy affair in that the detective not only seems vacant-minded at times, but also outwardly provocative and reckless as if his falling in love is not merely a figure of speech. Nor is it one-dimensional but is tied to his male pride and hubris--he's certain he's not "too old" "too old" as the father and fiancee claim, and that he's still compelling to young females. This is the old detective's self-deception that sets up the mystery, its investigation, and its resolution in part two.
The thoughtlessness of the mad genius is perhaps what we're observing, one whose deductive skills are so concentrated and potent that he can go without sleep, without vacations, (ironically this is his first in years) without food for as long as a case remains open. Which is probably the point--he has lost contact with reality, his body, his intentions, and his own movements (amnesia).
Whether this is a moral failing, a personal failing, or a mental condition is left up to the viewer, but the murders of the two youthful lovers and the terrorizing of a family speak for themselves. My guess is that all three of these vectors were operative in the detective's automatonlike crimes.
But Lewis' direction of part one seems to weaken this scenario because by showing the detective's response to the young woman as light, carefree, insignificant, and as no one's business, the effect of his falling for her seems diminished. And yet there are signs of near psychosis in this breezy affair in that the detective not only seems vacant-minded at times, but also outwardly provocative and reckless as if his falling in love is not merely a figure of speech. Nor is it one-dimensional but is tied to his male pride and hubris--he's certain he's not "too old" "too old" as the father and fiancee claim, and that he's still compelling to young females. This is the old detective's self-deception that sets up the mystery, its investigation, and its resolution in part two.
The thoughtlessness of the mad genius is perhaps what we're observing, one whose deductive skills are so concentrated and potent that he can go without sleep, without vacations, (ironically this is his first in years) without food for as long as a case remains open. Which is probably the point--he has lost contact with reality, his body, his intentions, and his own movements (amnesia).
Whether this is a moral failing, a personal failing, or a mental condition is left up to the viewer, but the murders of the two youthful lovers and the terrorizing of a family speak for themselves. My guess is that all three of these vectors were operative in the detective's automatonlike crimes.