A businessman, Mr. Dirkson, checks into his hotel room. A woman walks into his hotel room and insists that she's in the right room. She invites Mr. Dirkson closer to help with her zipper.
Carrie buys her usual espresso from the coffee stand. The radio announces a trivia contest with skydiving tickets as the prize. Carrie calls in and answers correctly to win. Carrie tries to convince Al to join her skydiving and conquer his fear of heights.
Al and Carrie arrive up at the crime scene where Mr. Dirkson's body lies. Al believes the murder is a botched robbery. Al asks the hotel manager for surveillance of the area but there are no cameras in the upscale tower section of the hotel. The manager urges them to finish with the room so that he can rent it out again.
At the station, Jay Lee fills everyone in on the background checks he ran on the employees of the hotel. The concierge, known for tipping off paparazzi to the whereabouts of celebrities, has also let famous people in through a back door. A paparazzi was there for four and a half hours shooting, but Jay is having trouble getting the photos.
In her lab, Joanne Webster shows Carrie that Dirkson was poisoned. The killer added strangle wounds later to make it look like an act of passion. Carrie believes that it was a trained killer.
The woman who killed Dirkson checks into a cheap motel. The motel desk clerk has a former police dog who barks at her, and she admits she has a joint in her bag.
Carrie and Al return to the crime scene. They realize that the blood was added to make it look like a burglary so that the poison would not be noticed. Carrie wonders if there is something else she didn't spot, and notices something off with the amenities on the desk. Carrie pries open the vent above the desk. Something is wedged in the duct, so she reaches in and pulls out a mobile data extraction device, used to copy and send data. The device's antenna was pointed upwards to the room above Dirkson's. Dirkson came back to his room early and surprised the woman planting the device.
Cherie searches Interpol for groups using both the poison Dirkson was killed with and the data extraction device. She finds that the terrorist group Alpha Five have been known to use both. Cherie says Dirkson just got in the way and he wasn't the intended target.
Cherie and Al visit the woman, Mrs. Hall, who is staying in the room above where Mr. Dirkson was murdered. She is signed in as a single guest but her room service charges indicate two people have been staying there. Mrs. Hall admits that she is staying with Kevin Purcell, who works press for the United Nations. He is covering a political activist from West Africa, Dr. Okoro Dimka. Dimka is responsible for attempting to take down the diamond monopoly. This isn't the first time he has been targeted: last winter his house was bombed.
The motel desk clerk knocks on the murderer's room door. He volunteers to help her smoke a joint. He sees gun parts laid out on the bed and asks about them. The woman says it's a toy for her nephew and invites him in. On her computer screen is a website about Dr. Dimka.
Carrie, Al, and Eliot Delson inform Dimka that he is being tracked and his schedule is known to the killer. They want him to cancel his public speaking dates but he refuses to leave in fear. His speech at the university is to be viewed around the world. He won't cancel but agrees to change the location.
Jay Lee obtains all of the photos from those who entered the back door of the hotel. He compares all of the photos to the Interpol database, and the killer turns out to be a woman, Jackie M. She is very dangerous and Interpol considers her a person of interest in eight assassinations in the last two years. All of her kills have been at everyday locations. Carrie and Al convince Eliot to let them set up a sting at the restaurant that Dimka was supposed to be dining at.
The woman is preparing drugs and a wig in her hotel room. The desk clerk is dead with a bullet hole through his forehead.
At the restaurant, everything is ready for Jackie to make an appearance. An old lady enters who is suspicious of the wait staff. There are multiple complaints about the drinks and food. She notices a waiter wearing a device inside his sleeve. The old woman is Jackie in disguise and she makes a break for it. Carrie runs after her but the only entrance is blocked by an undercover agent who Jackie poisons. Carrie, unable to get out of the restaurant, holds eye contact with Jackie through a window.
Back at the station, Jay finds a wi-fi signal that leads to a cheap motel in Brooklyn. Carrie and Al wait outside the motel for backup. Al and Carrie sing a song together before the SWAT team gets there. The room is empty except for a note about an Internet cafe, but the room will be searched further for any more information.
Al and Carrie fill Eliot in on the missing Jackie. Jay calls Carrie and informs her that the desk clerk was found.
Jackie is on the roof of a building overlooking Central Park. She tests out her sniper rifle by shooting a football in mid-air.
At the morgue, Carrie asks Joanne about any mysterious deaths that have come in. Carrie hopes that she can find evidence of Jackie killing someone else. A man from an Internet cafe was shot in the head the same way as the desk clerk. Al and Carrie visit the Internet cafe to look for clues. They investigate the computer that Jackie used and find details about Dimka's dressing room. They think that Jackie is going to sneak in as a journalist.
Jay calls Carrie and says that the search of the motel room turned up nothing. It was so clean that Carrie thinks that Jackie must have planted the note. Jackie never planned to disguise herself as a journalist.
In the auditorium, Carrie believes that she has identified a potential spot for Jackie to place her sniper rifle. Carrie ventures up to where Jackie is on the catwalk, passing a dead guard and his K9 unit. Carrie tackles Jackie right before she pulls the trigger. Al rushes Dimka off the stage to safety. Carrie and Jackie fistfight on the catwalk before Carrie pulls her gun out. Jackie says it could all have been avoided if the undercover agents knew how to make a cappuccino. She says it's all about the preparation and sucks the poison out of her ring, dying instantly.
Outside of the building, Jackie's body is taken away. A dog runs out of the building and up to Al. Carrie recognizes it and says she saw it dead a half hour ago. Jackie gave the dog a small coma-inducing amount of poison. She thinks Jackie may have also given herself a small amount. Al radios this information in.
The ambulance is later found with two dead paramedics and Jackie is missing. She is spotted boarding a plane to Columbia. The plane has already landed though and Jackie is gone. Al comforts Carrie with the fact that they saved Dimka's life.