A good murder mystery requires audience participation. Murder mystery films consist of two levels of detection. There are clues left for the detective and other characters, and those left for the audience. The viewer uses the genre to play detective, to investigate alongside the characters but also to observe the things which they do not. Every frame becomes a clue, which over times, adds to the tension and suspense of the film.
It’s particularly nerve wracking when we uncover something that puts the detective or our protagonist in danger, as we spend the rest of the scene waiting for them to catch up. We might have solved the murder before the detective, but we have not solved its fallout, which can be just as (or more) intense as the murder investigation. Scenes like this play with the dynamics around knowing and unknowing, specifically between what the audience knows and how/when the character will discover this same knowledge. A classic example of this comes from Silence of the Lambs, the scene where Clarice enters Buffalo Bill’s house.
The FBI have just closed in on the wrong house, and we suddenly realize that Clarice went to the correct place by herself and is now in danger. Although Clarice has just met Bill, we are already familiar with the character, and based on that, we know it’s just a matter of time before he attacks Clarice. The tension in the scene thus comes from when this attack will happen, not if. We know that Bill is guilty, but Clarice does not, as she is still preoccupied with figuring out if he might be the killer, whereas the audience has moved on from that.
The film presents several clues in this scene, but it is left unclear whether Clarice recognizes them as clues. It’s left unclear if she saw these details, or even if she saw them in the same way that we do. For instance, Bill has a painting of a butterfly or moth in his dining room, but Clarice never turns around to see it. The camera shifts towards the right so we can, but Clarice faces forward. There is also the plastic wrap, whose size suggests that it has been used on something big.
Then comes the decisive clue, the death’s-head hawkmoth on a thread. It is certainly the most obvious clue in the scene, connecting the skin suit with dressmaking and the moth. I would argue, however, that Clarice has already decided that Bill is the murderer before this moment, or at least her POV suggests this. The camera work is a surrogate for her critical detective eye, as it tries to capture both what she sees and in what way.
For example, the positioning of Clarice and Bill at the beginning of the scene says a great deal about the way they view one another. Because Clarice is on his front steps, she is shorter, smaller, and only takes up half of the frame. Bill, meanwhile, takes up the foreground and most the frame, signaling that he is in control of the situation and information. Likewise, when we get Clarice’s POV of Bill, he looks directly into the camera, is centered, and is blocked in a strange way. We only get part of his face, as the shot cuts off the top of his head, and later in the scene, part of his hand. As a result, we only see parts of Bill, which resembles the way Clarice is putting the mystery together. She has bits of information, but not the whole picture. She recognizes that Bill is a threat, or at least has threatening aspects about him, but she has not put these aspects together to realize that he is the killer.
Once in the house, the camera work changes to match the way Clarice studies the environment and Bill studies her. In Clarice’s POV, the camera shifts from right to left, never focusing on what Bill is doing. Likewise, Bill’s POV centers Clarice, while her POV is shown from her behind and to the left. This implies that Bill is focused on Clarice and everything she says, because he wants to uncover how much she knows. On the other hand, Clarice is still trying to connect this environment with Bill, which explains why her perspective focuses on the room more than Bill. Shooting from the back also suggests that Clarice wants to escape, but she doesn’t feel comfortable turning her back to Bill. In fact, the first time we see Bill centered in Clarice’s POV is right after she sees the moth, and has realized who Bill is. Only then does the environment become part of the background, as she has moved from investigation to defense mode. This moment is mirrored by Bill’s POV, which closes in on Clarice from the shoulders up as she finally puts the clues together.
And then the scene introduces a new twist by showing us a threat which Clarice does not know about: the gun in the kitchen. Clarice certainly suspects that he has a weapon, but the audience knows what it is and where. The only other person who knows about the weapon is Bill, so when Clarice asks if she can use his phone, he stifles a laugh. Whatever threat she posed to him at the beginning of the scene seems unimportant now that we have seen the gun. Bill doesn’t think of her as an FBI agent, but as a naïve girl asking to use his phone. He has also had more time to plan his next move, and he notices as Clarice slowly reaches to her holster and unclips it, but not subtly enough. Bill had the advantage of knowing that either Clarice would attack at some point, or he would attack her. Clarice has just put this information together, something which we as an audience have been waiting for. As such, the real tension in this scene isn’t if Bill will attack her, or if she will uncover the mystery, but if she will survive that discovery.