A Triannon crew which Enterprise rescues from a crippled ship turns out to be a group of religious extremists who hijack the NX-01 to eradicate the "heretics" on their homeworld. Furthermore, when the group's leader, D'Jamat, learns that Archer's crew has dared desecrate the Expanse's mysterious Spheres ? which the Triannons consider holy shrines of the "chosen realm" ? he demands that Archer choose a crewman to be put to death.