Shutter tells the story of photographer Ben (Joshua Jackson) and his new wife Jane (Rachael Taylor). The film begins with the couple's wedding, and the audience learns that they are planning to leave their apartment in Brooklyn for Japan, where Ben has been hired to take pictures for a particular client. The couple has made the decision to leave for Japan a few days early, renting a cabin so they can enjoy a shorter honeymoon. In the car on the way to the cabin, Jane gets lost and asks a sleeping Ben to check the map. While attempting to get their bearings, Jane sees a girl walk into the road. She hits the girl, and swerves off the road, crashing the car into a tree. They both fall unconscious.
When she awakens, Jane realizes the girl could very well still be laying in the road, and rushes out of the car to find her, Ben on her heels. They find nothing, and Ben thinks that the girl was already found and has gotten the medical help that she would need. He also thinks the injuries weren't life-threatening, as they cannot find any blood or evidence of a collision and wants to call for help. Later, help does arrive for them, and they are able to continue with their travel to the cabin, but Jane is haunted by the image of the girl. Ben's shoulder is bothering him, since the accident.
Jane tells him he needs to get it checked out. Ben chooses to ignore it, and at the cabin, they are able to enjoy a few day long honeymoon, and Ben wants to take pictures to record the event. Days later, Ben has to report for work with his friend Bruno (David Denman) Jane accompanies him but is somewhat left to her own devices as Ben needs to meet with the clients right away. We learn that Ben is fluent in Japanese, while Jane is not. Later, the pair are taken to their home, a building of which they are the solo occupants, and also the home of Ben's photography studio.
Jane notices an alcove where an old chair sits, and the image sticks with her. After meeting Ben's assistant Seiko (Maya Hazen), Jane again is left to her own devices while Ben works. She eventually gets the photos from the honeymoon, which are full of a mysterious light, and in showing the photos to Ben, makes the realization that something is off with them. Ben simply assumes there was an error with the camera.
Seiko mentions that the light is not from a camera error, but from spirit energy. Interested, Jane asks how she knows what the light is, to which Seiko responds that her ex-boyfriend runs a spirit photography magazine. She insists that Jane meet her ex the next day after work, and Ben, hearing that the girls have made plans to go out, jokes that "the girls have a date". That night, Ben, Jane, Bruno, his date and Adam (John Hensley) go out to a traditional Japanese restaurant. Here we learn that Adam is a model agent, but that his motives may not be in the best interest for the models.
The next day, Jane heads with Seiko to see the spirit photography magazine Seiko's ex Yoko (Eri Otoguro). While there, Jane learns that the magazine is mostly full of fake photographs, but that 1) a Polaroid picture cannot be faked and 2) a psychic named Murase (Kei Yamamoto) was written up by the magazine for his efforts in analyzing the photos. Later, Jane tells Ben about her visit and asks him to go with her. Ben's shoulder continues to bother him, and he goes to the doctor.
While there, he is weighed a couple of times, and the doctor tells him that there is no source of injury, but that he will give him some medicine for the pain. Rattled himself by the presence of the light in some of his work photos which have landed him in hot water with the client and a random encounter with 'someone' in the darkroom, he agrees to travel with Jane to visit Murase. Once at the home of Murase, Jane and Ben show him the photos and tell him that there was an accident and they believe this spirit may be that of the girl Jane hit. Ben serves as translator between the two. Murase takes the photos and begins to speak very emotionally, but Ben does not translate all of what he says, and tells her they are leaving. Ben does tell her that spirits bond with humans when extreme emotions (love, hate, anger, etc) are involved. Jane later looks at the photos of the project that were ruined by the light, and decides to go visit the office building in the photo that the light seems to be around. Armed with a borrowed Polaroid camera from Ben's studio, she heads to the building to take pictures and see if she finds any proof of the spirit's presence in the building.
When she gets there, she goes to the floor where the light has gathered, and takes pictures in the empty office. She has her first encounter, and learns the girl's name Megumi Okina through a picture frame that falls on the ground and shatters. Megumi is in the photo and when looking at it, Jane learns that her husband Ben took the photograph. When she confronts Ben about it, he admits that he and Megumi were involved in a relationship, but that she became obsessive and clingy, despite the fact that her traditional Japanese family did not approve of the pair.
If anything, the disapproval made Megumi even more clingy to Ben, who was trying his hardest to balance work and his blossoming relationship. Megumi's father, the main person who did not approve of the pair, dies, and Megumi becomes obsessive and even at one point becomes suicidal. Realizing this is too much for him to handle, Ben quits Megumi. Ben, admitting that he never loved her, gets Adam and Bruno to speak to her about the fact that the relationship is over and that she needs to stop following him around. Jane is upset with that, but decides they have to find Megumi. Ben talks to Bruno, who says that he recently saw Megumi on the street, she was pointing at him.
Adam is at his photography studio taking pictures of a prospective model, an Australian hostess that he mentioned at the dinner. He asks her to take off her clothing, except her underwear, and goes to get his camera from a box full of scantily-clad women. We get the impression that his motives at this point are not good at all. He begins taking pictures and starts seeing Megumi through the camera lens. He keeps stopping taking pictures, which begins to irritate the model. He is ready to take another picture, and the next thing we see is that the camera lens has shattered in his eye. Meanwhile, Ben and Jane are at Megumi's home looking for evidence of her location.
They find her, seemingly having been dead for a long time, as flies and decay have began, along with bottles of potassium cyanide strewn along the floor. They are still in shock over this discovery when Ben receives a call from Bruno about Adam's accident. Ben says that they will meet Bruno at the hospital. After being at the hospital for a while and Bruno does not turn up, Ben calls his cellphone in an effort to find out when he'll get there. Bruno answers but does not say anything, and as the camera pans out, the audience sees that he is slicing up photographs (into shapes of origami) with a razor blade and his hands are all bloody. Ben tells Bruno's voicemail that they desperately need him at the hospital because Adam didn't make it.
Ben and Jane leave the hospital and head to Bruno's home to see if he is there. When they arrive, they find all his picture frames are still on the walls, but the photos are all cut up on the table, and that the television is loud and blaring. Ben begins to look around for him, while Jane examines the photos on the table. She sees Bruno standing at the end of the hall, and it appears he is charging at her.
Ben calls out to him, and Bruno runs past Jane (who dives out of the way) and jumps off the balcony of his high-rise and goes crashing onto the concrete. He is dead. Ben is visibly distraught. Ben and Jane have decided to return to New York at this point, when in a voiceover, Ben says that Megumi's funeral will be in a few days, she will be cremated, and after the service, they can return home. When they return home to pack things, Jane opens a Fed-Ex that she has received containing photos of their wedding, and Jane makes the statement, "we aren't going anywhere".
Megumi is present in their wedding photos. They decide to leave the apartment and go to a hotel to spend the night. That night, Ben is haunted by images of Megumi in the room, her brushing her hair, her looking at him, her sitting on the floor, her initiating sex with him..
. all while Jane sleeps. He is very upset and somewhat frantic, and the ghost of Megumi confronts him with a kiss, and Jane wakes to find him choking. She watches him choke and attempts to help him, gets caught by the ghost in a curtain and smashed up against a window which cracks. In her desperation, Jane finally yells, "He didn't love you!" to which Megumi stops. Ben is gasping for air, but alive. At Megumi's funeral, her body is cremated.
Ben and Jane watch the process and hold hands. They return to New York, where seemingly all is over. However, this is not the case. Ben is out, seemingly at work, when Jane wants to take a picture of the rose petal shaped heart Ben has left her with a disposable camera. However, the camera is full of ready-to-be-developed pictures. She heads out to start her day and takes the camera with her, seemingly to drop it off at a developer.
When she returns home, she has the photos in an envelope. While preparing dinner, she opens the envelope and is shocked by what she sees. In the pictures, of her and Ben frolicking around while still in their wedding clothes, the ghost of Megumi is visibly in the photos, crawling towards the couple and eventually standing near a portrait of Jane that (seemingly) Ben took. Jane looks in Ben's belongings for the camera that he used in Japan, and finds the removable drive in the camera, which she loads into the computer, and is digusted by what she finds. When Ben gets home, he can immediately tell something is wrong with Jane. He asks her what is wrong and she opens the laptop and asks him what the photos are of.
.. and how he could do such a thing. We see the picture of Megumi, with Bruno and Adam, in a compromising position. Ben tells Jane that Megumi was crazy, she was obsessed and she wouldn't stop harassing him. So when Bruno and Adam got involved, Adam suggested giving her some pills that were like sleeping pills but a little stronger, and photographing her in compromising positions that they could use to blackmail her against her prim and proper family to finally leave Ben alone.
However, when the situation was happening, Ben took the photos but Adam and Bruno (more than likely drunk themselves) took advantage of Megumi and forced themselves on her. (The audience is led to believe this by the comments they make and the fact that they show the look on Ben's face). Ben admits to Jane that the situation got out of control but absolves himself of blame since he never touched her. Jane is digusted, and realizes that Megumi was trying to warn her of the man she loves, that Megumi did not want to harm her at all.
She starts to leave him, telling him that she needs time to think and then recants, saying she needs no time to figure out that he's not the person she thought he was and that she's done. Jane departs, leaving Ben alone in the apartment. Ben takes out a Polaroid camera and begins photographing the apartment looking for Megumi. He yells, "Me and you together forever, is that what you want? You got it!" The pictures show nothing, and in anger, he drops the camera and it takes a photo. He picks up the photo and looks at it, and it shows Megumi is sitting on his shoulders.
This explains his "injury" and why his shoulder has been hurting him so and why the nurse weighed him multiple times, his weight was that of 275, the weight of two people. In an effort to rid himself of her once and for all, hooks up a large amount of power to a photography light, which he puts to his neck. The power goes out in the building and we hear Ben's screams. The next scene is in a hospital. A nurse is wheeling a tray of food and drink into a room. We see the patient in the room is Ben, who appears completely catatonic, his head slung over and head closely shaved. The nurse injects his arm with a needle, sets the food down on the table and leaves the room, locking the door behind her.
As it closes, we see that the spirit of Megumi is hugging Ben, causing him to be slumped over..