The year is 1830. A body has been found hanging in the woods by the United States Military Academy in West Point. It's the body of one of the cadets, and it has somehow been mutilated with the man's heart surgically cut out from his chest. This murder could shake this still-young institution to the core, so a detective is hired to investigate and solve the case. The detective they bring in, Augustus Landor (Christian Bale), has no love of the military himself, and he can't seem to get much information from anyone. One cadet, however, is different from the others and proves vital in assisting Landor on his assignment: Edgar Allen Poe (Harry Melling).
This is not a movie based on a true story, but rather a fictionalized origin story for the writer widely considered to be the inventor of the detective fiction genre — a "Shakespeare in Love" for Edgar Allen Poe, if you will. Just as the character of Poe himself does to those around him, Melling's performance stands out from the moment we are introduced to him. Initially, I wasn't sure if it was necessarily a good form of standing out. Whereas the other British actors in the film are basically using their natural voices under the premise that British and American accents wouldn't have been that different in the 1830s, Melling goes heavy on an attempt at a Southern accent that takes a bit of getting used to.
After the initial shock of feeling "this guy seems like he's in a different movie than everyone else," however, Melling won me over when it became clear the movie he thought he was acting in was a much more entertaining movie than everyone else here was in. He does a good job building the psychology of an ambitious artist discovering more and more of the darkness that would define his work. He's also the only part of the movie that has any sense of humor, which is much appreciated in a film where every other actor seems to have only two modes: pensive and screaming.
Bale is fine as Landor. This isn't his biggest stand-out performance, and he's playing the same "pensive/screaming" notes as everyone else, but he's playing a character with enough hidden layers to allow him to play these notes with more finesse than his much less convincing co-stars. If there's anything to be gained from watching "The Pale Blue Eye" a second time, I imagine the value would mainly come in better appreciating the nuances of Bale's acting and how the ending revelations reshape the viewer's understanding of what he's trying to do and what problems are plaguing him.