Congressman Wendell Joyner shows up at a party for one of his friends, Dan Keppner, who is running for reelection in the House of Representatives. Dan is very intoxicated, and Wendell turns on the two men who are there with him, Harry Parmel and Raymond Dixon. He accuses them of getting Dan drunk because they knew drinking was his weakness. He then threatens to make a full report to the House Ethics Committee in the morning, but as he is yelling at them, he collapses. A young lady named Marta Craig, who had just left the room, opens the door and snaps a few pictures of Joyner lying on the ground with the other men around him. None of them notice her.
In Cabot Cove, a man named DeWitt shows up at Jessica's door. He tells her about Congressman Joyner's death and tells her that because the party does not yet have a nominee for the upcoming election, the governor has asked that Jessica fill the seat until the primaries are over.
A man named Joe Blinn picks up Jessica from the airport and takes her to the capitol building. She meets Dan Keppner there, and he tells her he will stop by later to discuss the Maine cannery bill. Then she goes into her office, where she meets Diana Simms, who will be her assistant. Diana tells her that she will be resigning because she knows Jessica will want to bring in her own staff. Jessica tells her the staff can all stay, and she throws Diana's resignation into the trash can.
Harry Parmel stops by with flowers and invites Jessica to lunch. She is about to accept, but she notices Diana shaking her head in the background, so she declines. After he leaves, Diana explains that Harry is a lobbyist who works for Pendrake Foods, one of the companies involved in the cannery bill.
When Jessica gets to her hotel, a man in the lobby is watching her but she does not notice.
Dan Keppner calls her from a place called Stockman's Bar. He tells her there is something he has to talk to her about. They plan to have breakfast together at her hotel in the morning. As Keppner leaves the bar, he is approached by Marta Craig. She shows him a picture that she has of the three men standing over the body.
In the morning, the man from the night before is still in the lobby of Jessica's hotel. He follows her, but she catches him and asks him why he's following her. He introduces himself as Lieutenant Avery Mendelsohn and tells her that he is trying to figure out who killed Joyner.
Mendelsohn explains that the coroner said the body was moved, and he is wondering why. As he explains, he nurses various aches and pains, including his feet and back. Then his stomach begins to growl, and he takes off, saying, "When my gut starts to growl, it's a sure sign there's a fox loose in the china shop."
Later that morning, Keppner wakes up in the street. Two police officers see him and realize that he's the guy they've been looking for. They take him in to Mendelsohn's office.
Mendelsohn gives him his jacket, his wallet, and a key. Keppner says the jacket and wallet are his, but not the key. Mendelsohn then explains that the key belongs to Marta Craig, who was found beaten to death in her apartment the night before. Keppner's hands are bloody, as though he had been punching something or someone, and his jacket and wallet were found in Marta Craig's apartment.
Jessica asks Diana about Joyner's plans for that evening, and she says she remembers Harry Parmel inviting Joyner to a party that night. However, she tells Jessica that Joyner declined the invitation.
On her way to a committee meeting, Jessica is stopped by a young man, who introduces himself as Thor Danziger from the Ecological Foundation. He asks to see her, but Diana gets rid of him. As they walk away, Jessica expresses concern that they were rude to Danziger. Diana says they already had their chance.
At the meeting, Jessica asks Diana if she heard from Keppner, but Diana says no. Dixon opens the meeting by introducing himself as the vice-president of Pendrake Foods.
After the meeting is over, Joe Blinn tries to talk Jessica into having lunch with the owner of a popular feminist magazine, Kay Sheppard. Jessica tells him she doesn't have time.
When she gets back to her office, Mendelsohn is there. He tells her that they are holding Keppner, but he hasn't booked him yet because his stomach is bothering him and it just doesn't seem right. Jessica accompanies him to the station, where Keppner tells her about moving Joyner's body. He then explains that Marta was at the party and tells Jessica about seeing Marta outside the bar. He says when he saw the picture, he did go back to her apartment with her, but he said all he had was ginger ale, and he was not drunk. He begs her to believe him.
Jessica goes to see the body and Marta is so badly beaten that even Jessica has to turn away. She composes herself, then tells Mendelsohn that Keppner did not kill her. There would have been more blood on his shirt if he had, and there would also have been makeup on his hands. The lieutenant admits that she's right.
Back at her office, Jessica talks to Diana and Joe. They tell her that Keppner quit drinking for several years but started again after his wife left him with their children. Jessica asks Joe to get her some information on Marta Craig and her relationships to the men at the party.
Diana Simms goes home and finds Thor Danziger waiting for her. After hugging him, she asks what's going on. He tells her he got a package in the mail and shows her pictures of himself and Marta Craig in bed together. Diana says that she has already seen them and knows they are fakes. There is also a note that says to stay away from Mrs. Fletcher.
Jessica and Mendelsohn go to Marta's apartment so Jessica can look around. While there, she sees a picture of Marta and some of her friends. Included in the picture is Diana Simms.
Jessica has lunch with Kay Sheppard after all. Kay offers to give her some information about Marta's murder in exchange for an exclusive if Jessica helps solve the murder. Jessica agrees. Kay tells her that she saw Marta and Dixon in a horrible fight outside the Watergate. She says that "Dixon looked mad enough to kill."
Back at her office, Joe tells her that he couldn't find much information on Marta Craig. She had six jobs in the past four years and did the "party circuit" almost every night of the week. He also tells her that Diana called in sick after lunch. As he leaves, Jessica asks him to find out more information about Marta by the next day.
Jessica looks up Diana in her address book, but is interrupted by a knock at the door. Dan Keppner comes in and tells her that he's decided not to seek reelection. He thinks he's in over his head with his alcoholism and the problems with his wife. Jessica tells him to go home and talk to his wife and find out what she thinks, and he agrees to do it. He thanks her and leaves.
Jessica stops by Diana's place to ask her a few questions. She notices an ashtray with cigarettes in it and realizes that Danziger is there. She calls Diana on it and Danziger comes out. He asks how she knew it was him, and she tells him that she noticed his tie pin matched the emblem on the cheerleading outfits that Diana and Marta were wearing in the picture. Diana explains that they used to be good friends with Marta until she got involved in the party circuit and started hanging around people like Harry Parmel. Danziger tells Jessica that he knew he would be at the top of the list of suspects because of the faked pictures so he pretended not to know Marta.
They take the pictures to Mendelsohn and explain their story. He tells them to remain available and lets them go.
Later, Joe gives Jessica a ride and he relates the information he found about the last day of Marta's life.
At the capitol building, Jessica runs into Raymond Dixon, who wants to talk to her about the cannery bill. She asks him instead about Marta Craig, and he says he barely knew her. Jessica comments on his ability to lie without showing outward signs of it. She then tells him she knows about his fight with Marta Craig. He gets angry and stalks off.
Jessica goes to her office but before she goes in, she stops and turns around. She tells Diana she has to go somewhere. Diana warns her that the meeting to vote on the cannery bill starts in less than 2 hours, but Jessica just tells her not to let the voting start without her and leaves.
The meeting starts without Jessica, and Dan Keppner keeps talking, trying to stall for her. Jessica finds Joe and tells him that Kay Sheppard said that an old boyfriend of Marta's was hanging around outside her building when Keppner got there. He saw Keppner go inside with Marta, then a few minutes later, he saw another man go inside. Jessica says he didn't get a good look, but it must have been Dixon. She says that Marta must have been blackmailing him, too, and that was why they were fighting. She tells Joe to meet her and Kay after the committee meeting so they can call Mendelsohn and try to get a court order to search Dixon's penthouse. She then rushes off to the meeting.
At the meeting, she points out that there are seven abandoned canneries in the state of Maine, two of which belong to Dixon's company. She tells Dixon that his people have taken a lot out of the state of Maine and they should give something back now. At the end of her speech, everyone applauds.
Meanwhile, Joe Blinn is breaking into Dixon's penthouse. He gets caught by Mendelsohn as he tries to plant the pictures from the party. Jessica shows up a few moments later, and Joe tries to deny he killed Marta. Jessica points out that when she first met him, Joe was wearing a pair of very fancy driving gloves, but when she saw him that morning, he no longer had them. She also tells him that Dan never told the police where he was picked up, but in the car that morning, Joe said he was picked up outside Stockman's Bar. Dan was just wandering around and didn't know where he ran into Marta. The only way Joe could have known was if Marta told him. He is arrested and Jessica and the lieutenant go out for lunch.