Fugitive security guard Stanley Tweedle, love slave Zev Bellringer, and love slave robot head 790 are thrown together by fate and on the run from His Divine Shadow after stealing The Lexx: the most powerful destructive force in two universes.
As things settle down on the Lexx, the crew realizes Kai needs a constant supply of proto-blood to continue to function in the real world. Stanley and the others undertake a desperate mission to Kai's wrecked home world in search of a way to extend Kai's existence.
Out of energy, the Lexx is forced to land on a planet to replenish its energy supply. Zev and Stan bury the apparently dead Kai, before they discover an outpost occupied by lunatics led by the manic Bog.
To resupply the protoblood that sustains Kai's life, the crew of the Lexx travel back to the Cluster but find the planet deserted. The population was killed in "The Cleansing", in preparation of the birth of the Giga Shadow, the last survivor of the insect wars and sworn enemy of humanity. The crew try to destroy the Giga Shadow with the help of Yottskry (played by guest star Malcolm McDowell), a defecting priest of the Divine Order.