Terence.Fletcher.J. K. Simmons plays an abusive authority figure very convincingly. He is arguably even more terrifying and imposing than R. Lee Ermey in Full Metal Jacket or Clancy Brown in The Shawshank Redemption, and in fact even belittles a chubby trombone player and gives him a silly name ("Elmer Fudd") in much the same way the drill sergeant from the former movie calls one of his chubbier recruits "Gomer Pyle". Anyone that has ever had an abusive teacher or other authority figure will immediately find Fletcher's presence extremely frightening.
The scene where Fletcher isolates Andrew, Ryan and Carl from the other students while cursing and screaming at them to drum at his ludicrously fast tempo. When Andrew has finally gotten the tempo Fletcher gets right up next to him and screams “FASTER!” repeatedly. At some point he grabs one of the drums and throws it against the wall while continuing to scream at Andrew. A dark low bass starts playing near the end to emphasize the horror of this scene. By the end Andrew has completely destroyed his hands and splattered blood all over the drumset.
Part of what makes Fletcher's fury so terrifying in this scene is how slow burn it is. He starts out as relatively calm, almost bored and just barely manages to swallow up the churning rage inside him when the drummers are out of tune, eventually screaming "motherfucker" and kicking a chair when it keeps on going long enough. Then, Fletcher is back to the calmer version of himself, realizing how this entire process of simply finding the perfect drummer could take all night.
Though there is ambiguity as to whether or not Fletcher's abuse was what accelerated the deterioration of Sean Casey’s mental state, being a parent, sibling or other loved one having to walk in and find their loved one dead after taking their own life, and gradually coming to realize they were likely driven mad by months, if not a year’s worth of psychological and physical abuse that reduced them to a self-hating shell of a human by a man who did so for something as banal as creative integrity. Fletcher was right to recognize that he had enemies, and he was lucky that Casey’s parents just wanted him fired, because anyparentless hinged would or couldhave retaliated regardless as to whether or not their child died, or what consequences may come.
Andrew's out-of-nowhere car crash. As with many car crashes, it all happens so fast, and it's shot from inside the car, so we see all the car damage up close. Andrew also has a bloody head and hand after escaping the car.
Andrew’s injuries shown as he desperately tries to perform after the aforementioned crash, including a compound fracture in his finger! Is it any wonder why he couldn’t continue?
The ending is made of this. It starts off triumphant with Andrew getting the jump on Fletcher by starting to play "Caravan", and he looks like he's enjoying himself drumming for the first time in the film. But once he starts improvising, he gets sweatier and bloodier, wearing the pained expression he wore so often whilst drumming at all other times; and then, Fletcher starts conducting him. Rather than playing as he pleases, refusing to let Fletcher have control and completing his revenge, Andrew obeys his instructions. Fletcher has him utterly and totally in his grasp now, and the implications of that are simply terrifying.
The famous "Not my tempo"/"Rushing or dragging?" scene, in which the true extent of Fletcher's abusive nature is revealed. At first, he coaches Andrew firmly but relatively gently, but after letting Andrew think he's doing well for a minute, he throws a chair at his head, screams at him, slaps him multiple times, threatens to "fuck [him] like a pig"; by the end of the scene, it's no wonder Andrew is in tears. The fact that the other students don't speak up hints that they've seen this before and know not to intervene, and/or that they're too afraid of Fletcher to do so; a chilling encapsulation of the deeply cruel environment Fletcher creates. The framing adds to this: much of the scene is shot in close-up, so when Fletcher's screaming in Andrew's face, he's screaming in the audience's face too, and it is deeply, viscerally uncomfortable.
