While on course for the Alpha Quadrant, Voyager is suddenly pulled into an area of space absent of any matter, and in which a number of other starships have been trapped. In the chaos of their arrival in this area, Voyager is set on by another ship that disables its shields and transports away its deuterium stock and other supplies before moving away. Captain Janeway orders a counter-attack, but the ship has moved off to warp.

They are approached by another ship which hails them. Its captain, General Valen, explains they are in "The Void", and while impressed with Voyager's response to the attack, believes they can help if they were given some of the ship's photon torpedoes. Janeway refuses, unsure of Valen's purpose. Valen departs with his ship.

Later, Seven offers a potential way out of the Void by recreating one of the funnels to normal space that brought them there via shield modulation. However, though they nearly escape, they are drawn back in forcefully at the last moment, damaging many of the ships systems. Janeway asserts they must find the ship that stole their supplies to sustain themselves. Tracking the ship, they find it has been attacked with complete loss of life, and all of its supplies, including those belonging to Voyager are gone. However, among the ship's casing they find a wounded humanoid creature that they bring back to Voyager for treatment.

The crew recognize damage to the ship belonging to Valen's species, and track his ship down. They disable his shields and demand he return their supplies, but Valen refuses. Janeway orders them to recover their supplies and considers taking more, but decides against it. They find they have recovered less than half that was stolen, and First Officer Chakotay suggests they may have to resort to stealing from other ships to survive, an action Janeway refuses to take. Instead, she offers the idea of creating an alliance with the other ships to pool their resources so they may all escape the Void. Voyager begins contacting the other ships, many who agree to the alliance, and the various crews start sharing their resources and technologies, with Voyager itself gaining several useful upgrades for their journey home should they escape. When Voyager and another alliance ship stop Valen from attacking a recently arrived Hierarchy vessel, Valen reluctantly decides to join this alliance.

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Wikipedia