Voyager is visiting a planetoid to look for Dilithium. Janeway finds Neelix has turned her private dining room into a galley. She has a private dining room for eating rations in? She has a private dining room that big?? Grief.
Chakotay, Kim and Neelix beam down to the planetoid and wander around. There's a corridor which looks suspiciously like the corridor from the polaric energy station in the previous story. Tsk. None of them can find any dilithium, but Neelix detects something alive. Which promptly zaps him. Tuvok finds him convulsing and they beam up to sick bay.
Ohhh, look, the promo for Utopia. Way to spoil the ending, Prime!
HoloDoc reports that Neelix's lungs have been removed. While HoloDoc and Paris fight to save Neelix's life, Janeway takes a team to the planetoid to look for Neelix's lungs. HoloDoc sets up a pair of holographic lungs, but this means that Neelix will have to remain motionless on the bed for the rest of his life.
On the planetoid, the away team find a bunch of preserved organs, unfortunately none of them Neelix's lungs. They pursue someone, but he gets away, and a ship leaves the planetoid in a hurry. The team beams up and they set off in pursuit.
Hmm, Neelix seems bitter. The analysis of the device the alien dropped reveals it's a highly tuned scanner for harvesting organs. Also, they find an asteroid, and fly into it looking for the alien ship.
After Neelix panics and HoloDoc has to sedate him, the hologram angsts to Kes, who gives him a rousing pep talk.
Voyager locates the alien ship, and they beam the two occupants on board. Said aliens are, of course, the Vidiians, who have a deadly degenerative disease called The Phage and must harvest organs from other species to survive. Sucks to be them. You'd think Neelix would know about them at least. Unfortunately Neelix's lungs have already gone to a new home. Janeway says she has to let them go with the warning that she'll use deadly force to protect her crew.
Y'know, no one seems at all concerned about the pair possibly passing the Phage on to the Voyager crew. Hmm.
The Vidiians help by transplanting one of Kes' lungs into Neelix, and Kes volunteers to study to be the HoloDoc's medical assistant.