At 48 words, the logline is t-o-o long. ( I conclude from? my statistical analysis of hundreds of loglines, that the maximum tolerable length? is 40 words.? See the chart I posted in a thread? in 2016.? I've added 140 more loglines to the sample since; the distribution and conclusion holds.)
So where to trim?? Well, I suggest "with a dark shameful past" is extraneous.? For the purpose of a logline, "dark past" must signal that it will come back and bite the protagonist in the present; it will threaten his chances of succeeding.? It must create conflict in the present and suspense as to future.
And more interesting than the "dark past" is that he's pitted against his old Civil War captain.? I would refocus the logline around that conflicted relationship.
Making the marshal his old Civil War captain is interesting.?
Anyway, it's your story.? You've already written the script.? So whatever.
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