It's part of the procedural...
This slasher takes place in 1946 Texas, 30 years prior to its release. The featured serial killer wears a white hood on his head and has a loony's M.O. He attacks his victims in creative ways and often takes pleasure in making them suffer. He rarely uses the same weapon, as if experimenting with death. The camera loves him and studies his every move; an interesting cinematographic choice.
We’d feel more vulnerable if our main protagonists were future victims instead of policemen. We are unfortunately expected to keep up with their procedural and their soundtrack right out of a spy film. Here and there, a narrator with a deep foreshadowing voice compensates to restore the wasted build-up, reminding us that we are watching an evolving tragedy.
Some actors pull it off better than others, doing what they can with stiff characters. Many exist only to die and the rest could use more chemistry. The Town That Dreaded Sundown has light humor but an otherwise ruthless tone. It is presented as a whodunit, is gorier than terrifying and more exploitative than story-driven. It is a generic succession of rigid dialogue and shocking murders.