NX-01 orbits a strange dark planet. In the lounge !Mayweather and (ship's champion) !Reed play 2D chess, dismissing the game as predictable. Something's not quite right, particularly when they talk about "observation without interference" and how physical species all look alike. Then "somebody always dies" pretty much caps the idea. Shpodding from the planet are Trip and Hoshi, filthy from treasure hunting around Klingon latrines. Trip coughs uncontrollably and the shpod lands in a medical emergency. Phlox comes for samples as Trip feels gut-punched by a Tellarite and Hoshi starts to cough.

!Mayweather and !Reed talk about how, in their alien observations over the last eight hundred years or so, the Klingons and Cardassians reacted to the infection (killing the infected, go figure). !Travis pesters Trip to the point that he closes the biohazard window on his annoying questions. !Reed pesters Phlox similarly, who shoos him away. Table-terror Trip and aikido black-belt Hoshi discuss the Andromeda Strain and breaking arms in Starfleet training. Phlox determines the affliction is a silicon-based virus and ionizing radiation will kill the virus but similarly the host. (!Reed and !Travis note the pathogen is identified only 37% of the time, but still don't consider humans as "elevated intelligence.") The death-counter starts as Archer visits sweaty Trip and orders rest but (blowing 10000 inconspicuous years) !Phlox and !T'Pol interrupt with weird questions (kudos to good intercharacter continuity while switching corporeal actors).

Hoshi wakes from multilingual nightmares and escapes quarantine. Almost out an airlock, Trip stops her and to decon they return. Archer has D-Deck sealed off and orders Trip and Hoshi sedated. !Travis talks to !Reed who suggests speaking unobserved by hijacking Trip and Hoshi, who Phlox promptly spots unsedated. !Archer and !T'Pol show up but the doctor figures them out. By now they're impressed since only one race in fifty detects their presence. Phlox calls their unwillingness to help "appalling" and gets mind-wiped.

Archer and Phlox don spacesuits to take dying Trip and Hoshi to sickbay (finally dark). Archer exposes himself to stab Hoshi with a heart needle and jumpstart her but she dies. He tells T'Pol to take over. Trip flatlines but (not exactly himself) comes out of it. !Trip identifies himself as an Organian and !Hoshi joins in the zombie-chat. Archer says they're not more advanced and should try a little compassion. !Trip defies the protocol and everybody miraculously recovers. !Travis feels the humans are unavoidable and worth first contact. !Reed says with only five thousand years to prepare, they better get started.