The crew of Voyager are foraging for food on a planet pointed out by Neelix, when Voyager, in orbit, detects a cloaked Kazon ship. Chakotay is left behind to search for Seska, who almost shoots him for an enemy. As soon as he finds her, two Kazons injure Chakotay slightly, and both are dispatched before they leave the cave.
When back on Voyager, Seska makes Chakotay his favourite, mushroom soup. She begins to tell him that she and several other Maquis had taken the food to make the soup from Neelix's kitchen. At hearing this, Chakotay becomes enraged and disgusted. He asks her how she could carelessly take food from the rest of the ship. Minutes later, Neelix calls Chakotay and tells him that people have stolen food and that he suspects Seska. Chakotay confirms his suspicion and says that everyone involved will be disciplined. He tells Seska that she and the others involved, including himself, will have their replicator privileges withdrawn for two days. She says that they will not agree, to which he replies that he will have them all thrown into the brig. He then walks over to the window in his room and stares out at space. Seska comes over to him and Chakotay tells her that they both agreed their relationship wouldn't work out. Seska becomes annoyed and leaves after this statement.
A few moments later, Voyager detects a distress call from a Kazon-Nistrim ship, one of the most aggressive and violent sects of the Kazon order, and discovers that a piece of equipment has caused a catastrophic failure on board, killing all but one of the crew, who is comatose. On investigation, they find that the equipment bears resemblances to Starfleet technology, and after narrowing down from one of three theories of Tuvok's, they realize that the technology must have been given to the Kazon by a member of the crew during the visit to the planet, and that this member of the crew must have been alone on the planet's surface. An engineering team goes over to the Kazon ship, but returns to Voyager when they discover that they will have to determine what happened to the ship from Voyager, because the Kazon ship has unstable elements in it. However, Seska decides to take matters into her own hands and to try to figure out what happened on the ship (she does this, supposedly, to prove her innocence), she crosses over to it, even though it isn't safe. While on the ship, Seska is injured and gets reprimanded by her superiors when she returns.
Captain Janeway realizes that the comatose Kazon might be the only chance of finding out how the technology came into their possession. Another Kazon ship arrives, and after attempting to convince Voyager to stop meddling in their affairs, the Kazon captain, Culluh demands to see his crew member. Culluh and his bodyguard arrive in sickbay, where The Doctor explains about the accident and the nucleonic radiation from the console. The Kazon want to be left alone with the man, so Janeway talks to The Doctor in private, not eager to release their patient into Kazon hands. Janeway prepares to inform the Kazon of her intentions when Culluh's bodyguard takes out a small needle. Tuvok attempts to intervene, but he injects a neurotoxin into the patient's blood, killing him instantly. Disgusted, Janeway orders Culluh and the bodyguard off her ship.
Kes finds Seska has Cardassian blood. Seska claims it was a blood transfusion from a friendly Cardassian woman, but Kes is doubtful. Investigations reveal that a message was sent to the Kazon to organize a meeting on the planet. The nature of the time of the message implicates a member of the engineering team. The two most-likely suspects for the crime are Ensign Seska and Lt. Carey. The senior crew members set a trap to identify the crew member, and Ensign Seska falls for it. She explains that the Kazon are a powerful race in this quadrant and by giving them technology, Voyager will gain a powerful ally. Janeway retaliates by informing Seska that such careless sharing of technology could change the balance of power in the Delta Quadrant, and is forbidden by the Prime Directive. Chakotay accuses her of being a Cardassian spy on his ship. Seska then says that living with Starfleet has made him soft, and that she has no clue how she could have ever loved him. Seska, however, has pre-programmed a transport into the computer, and is beamed to a Kazon ship.
Voyager is initially sent in pursuit, but more Kazon ships arrive and Voyager retreats. Chakotay asks Tuvok if he had been naive for being fooled by Seska. Tuvok states he was fooled, as well. This pleases Chakotay, as he replies, "Misery loves company, Tuvok!"