 Enterprise has located a Xindi ship on the surface. Archer, Reed, Sato and T Pol start investigating, only to find a dead body and the place scorched. T Pol notices something s wrong when she feels strange and sees the other away team members change into aliens. They don t speak a word English, don t know who they were and have the irresistible urge to go to the city Urquat. A rescue party is able to take Reed back to Enterprise, where Phlox finds out a mutagenic virus caused the changes. While Phlox searches for a cure, suddenly two alien ships show up. Their goal is to prevent an outbreak of the virus with any means necessary.