Episode 4 of "Lexx"
s01e04 Giga Shadow
Title: Giga Shadow
Original Air Date: 08/09/1997 on TMC
Plot Outline:
Kai is running out of protoblood, and a desperate Zev forces Stan to set course back to the Cluster through the fractal core. When they arrive they find they entire planet barren - everybody killed in "the cleansing", in preparation of the birth of the Gigashadow.