||Voyager is running low on Dilithium, but fortunately Neelix claims to know of a nearby asteroid where there is a pleantiful supply of the stuff. He goes on the away mission and quickly wanders off alone. Detecting dilithium, Neelix works his way towards the source - only to be confronted by two aliens, one of whom shoots him with some device which leaves him flopping around on the floor.
The others rush him back to Voyager only to find that Neelix's lungs have been surgically removed. The EMH rapidly generates a pair of holographic lungs for him. Whilst this saves his life, the limitations are severe; for as long as he is dependent on them, Neelix will have to remain in sickbay, clamped down on the bed with his chest held perfectly still.
Janeway leads another away mission to the asteroid where they find an alien facility and wound one of the aliens, forcing him to drop his weapon before he escapes in his ship. Voyager follows the ship whilst they examine the weapon; part tricorder, part transporter, the device can scan a person, analyse their anatomy, and beam out selected organs. The aliens each appear to be a hodgepodge of stolen body parts from different species.
Voyager chases the alien ship into another asteroid, but this one appears to be lines with natural mirror surfaces, casting hundreds of reflections all around them. They come up with the solution of simply firing a phaser on a low setting; the beam bounces from wall to wall, only stopping when it hits the real alien ship. Beaming the aliens aboard, the crew learn the horrific truth; these Vidiians are infected with an incurable disease which eats away at their organs. Using their advanced medical technology they steal organs from alien species, modifying them so that they can replace their own dying parts. Neelix's lungs have already been modified and implanted, and Janeway must face a choice; taking them back would mean murdering one of her prisoners. The man even offers to volunteer, telling her it would be a relief to die and finaly be rid of the life he is forced to lead. Unable to take him up on the offer, she sees no choice but to let the Vidiians go, but issues them a stark warning; in any future encounter she will use lethal force to defend her crew from any further harvesting.
About to leave, the Vidiians realise there is another choice; their medical technology is advanced enough that they might perhaps be able to modify a lung from one of Voyager's crew to be suitable for transplant into Neelix. Kes volunteers, and the procedure is successfully carried out. Neelix, now with one lung, makes a full recovery and everyone goes on their way.
||A mix of good and silly ideas, this one. First off, you have to wonder if the writers had already recognised how pathetic the Kazon are even this early, as the Vidiians seem clearly to be an effort to find a new standard bad guy for the episode. As bad guys the Vidiians are interesting; not evil as such, just driven to be evil through desperation. They literally face the choice of stealing other people's organs of dying, and you can hardly blame them for not choosing death. Where it all falls down a bit is that no other alternative is ever considered; we already have artificial replacements for a few organs, and more on the way. Can the Vidiians not do likewise? And our medical and genetic technology is advancing so fast... talk of using a pig's organs for Human transplant never panned out, but how long until we can genetically modify animals to make such a thing possible? For that matter, how long until we can simply clone and grow replacement Human organs in some vat of chemicals? Truthfully we will probably have such capabilities long before we will ever have warp drive or the transporter. The Vidiians are already stated to be able to modify organs so much that they can transplant from one species to another relatively easily... so one would expect that they can take and modify animal organs just as easily. Yet they take organs from sentient beings, and only sentient beings. There's no plausible scientific reason why this should be so, but the episode could have posited that the Vidiians find animal transplants disgusting, or it's forbidden by their religion, or something. They could have depicted that as a schism in the society; perhaps there could have been those Vidiians who did use animals, and were thus despised and mistreated by the majority. This could even have provided the answer for Neelix, with him being given an animal heart by one of these Vidiians - thus leading the majority to look at Humans as being morally repugnant themselves. All of this could have been gone into and made the Vidiians a far richer, more believable species... but instead we get the frankly stupid "asteroid hall of mirrors", which does basically nothing for the plot and honestly comes across as if the episode was running short and they wanted something to fill up a few minutes.
The Kazon and Vidiians make an interesting contrast. The Kazon were shallow - Klingon wannabes with no real potential for growth or interest, no way to add depth to the show. The Vidiians on the other hand... they had a good deal of potential, and could have become something really interesting, but although Voyger would bring them in a few times and get one or two good moments out of them, they just seemed like a big bag of potential that the writers never bothered to explore. In the end, both species were written off in favour of a mix of baddies of the week and the Borg as a recurring threat; many years later we would get an offhand remark that the aliens in Think Tank were responsible for curing the Vidiians. An unthinking end to a species that could have been so much more.