A genetic research station, Darwin, has created perfect human telepaths, immune to disease, advanced in intelligence, gifted physically and intellectually, mature, yet they have a system to fight off illness by way of antibodies that affect human dna, causing those infected to age at a rapid rate. Before this was known, Dr. Pulaski decided to risk being exposed to what killed a crew on another ship, by examining one genetically created child on a shuttlecraft, Data operating the controls, becoming infected with the old age disease. Picard and company are in a race against time (in more ways than one) to find a "cure" for the disease or else lose Pulaski and the other Darwin geneticists to certain death. Once again, scientists fooling around with genes/dna, playing God, pay a price for doing so. The very beings they create will have to remain in isolation the rest of their lives because the bunch is "too perfect". Fascinating use of the transporter (and amusingly points out Pulaski's repulsion for the device) as a possible cure due to a bio-filter system that "weeds out" any known diseases that might threaten to harm the crew of the Enterprise. A sample of Pulaski's dna will be detrimental to this experiment's success and salvation of other lives not just hers. This episode is what you might call a Diana Muldaur vehicle as she becomes the Chief Medical Officer replacing Dr. Crusher and her stubbornness and traits similar to Bones obviously intentionally pays homage to the iconic McCoy character; she gets center stage as the story is catered to the Pulaski character. Her disputes and debates with Picard (and the revelation that she jumped at the chance to work on the Enterprise because of the opportunity to serve with Picard) are really what make this episode, Unnatural Selection, such a treat. One could poke and prod at potential scientific flaws that might expose themselves, but ultimately I watch the show for the stories and the characters. This episode would make a nice companion piece to the Star Trek Original Series second season classic, The Deadly Years.
Review of Unnatural Selection
