Sometime later in another part of the Delta Quadrant, Seven of Nine reports to Captain Janeway that sensors have detected a planetoid with large dilithium deposits within easy reach below the surface. Once Voyager arrives and confirms the find, the planetoid begins to become unstable and explodes in a cloud of explosive gases. The gaseous cloud also prevents Voyager's warp and impulse drives from functioning properly. Suddenly (from behind the remains of the planetoid) a ship emerges and immediately attacks Voyager. Seven recognises it as belonging to Species 4228 (the Zari) who she explains are technologically advance and very warlike. They are known to be a race of bounty hunters. With the more powerful vessel causing serious damage on Voyager, the Zari Captain hails Voyager and demands they surrender. But Janeway takes a risk and launches photon torpedoes at the Zari, hoping that the surrounding gases will cause an explosion that temporarily disables the unexpecting Zari ship and at the same time, allow Voyager to warp away to safety. The plan works and soon Voyager is at warp speed. However, the crew is left wondering why the Zari ship doesn't pursue? Sensors soon show the reason - the Zari have a whole fleet of ships in the area to offer reinforcement!
Several days later, Janeway is alone in the mess hall pondering over the problem of how to continue avoiding the pursuing Zari. Suddenly, Curos appears in the mess hall and tells Janeway that he knows about Voyager's problem and that he's the answer. He further explains that he isn't really on Voyager, but just an "isomorphic projection." He explains that he and his group of travellers go around the quadrant looking for puzzles and problems to solve, to which Janeway responds by referring to Curos's group as a "think tank." Curos offers to help Voyager with its Zari problem. He invites Janeway and one other crewmember to visit him on his ship.
Voyager arrives at the designated coordinates and Janeway beams over to Curos's vessel with Seven. Intrigued by the fact that Seven is from the Borg collective, Curos introduces them to the other members of the "think tank" which include the water-dwelling creature and robot seen in the opening act of the episode. Although they are vastly different, the members of the group communicate through a device located in the centre of Curos's bridge. The robot asks for the opportunity to communicate with Seven and begins a telepathic conversation with her. Meanwhile, Curos tells Janeway about some of the recent successes that his group has achieved - including a cure for the Vidiian's phage disease, which really impresses Janeway. The meeting ends with Janeway somewhat sceptical about what Curos may want in payment for helping with the Zari problem but willing to consider it for the time being.
Later, Curos again appears on Voyager as an isomorphic projection and presents Janeway with a list of things they would like as compensation for helping Voyager. Most of the items are things common items but the last one surprises Janeway as Curos wants Seven of Nine to join his group. Janeway's refuses outright but Curos suggests that Janeway speak with Seven to find out her feelings on the matter. Janeway does so and ends by telling Seven that whatever she decides, it should be based on what she wants and not what would be best for Voyager. Seven decides to remain on Voyager, despite a strong pitch by Curos that she cannot achieve perfection if she remains on Voyager. Curos is unhappy with Seven's decision.
Zari ships begin to converge on Voyager. As Voyager is attacked, Curos's projection appears on Voyager's bridge and taunts Janeway about his ability to help Voyager if she would try to convince Seven to join his group. Janeway steadfastly refuses as Voyager outmanoeuvres the Zari and makes its escape. Meanwhile, Curos tells his comrades that they will wait for the Zari to disable Voyager and then just take Seven.
Sometime later, Voyager sets a trap for a lone Zari ship and captures it and its two occupants. Although the Zari are completely uncooperative about telling Janeway who is paying them to hunt down Voyager, a search of their ship's computer reveals that it is Curos and his "think tank" who are the Zari's customer's. However, the Zari do not know that Curos is the one who has hired them and believe the Malon hired them! Janeway convinces the Zari to work with her to put a stop to Curos.
Later, a renewed Zari attack finally manages to disable Voyager and with the ship near to destruction, Seven leaves in a runabout and agrees to join Curos. The plan seems to be going well but Curos becomes suspicious when the Zari seem a little too anxious to conclude their business deal. He has the robotic member of the group force a telepathic link with Seven to learn Janeway's plans but Voyager is ready to transmit a hidden signal through Seven's neural transceiver that disrupts the telepathic communications device on Curos's ship, making it impossible for the members of the think tank to communicate with each other. Left stranded in space, Curos's ship now comes under attack of the Zari. Meanwhile, Seven has been transported back to Voyager and the ship departs the area at warp speed.