Lexx (1997)

Four misfit characters inadvertently steal the most powerful weapon of destruction ever made: a Manhattan-sized, sentient, genetically-modified insect named the Lexx. The four main characters include: Stanley Tweedle, the bumbling, self-serving captain of the Lexx; Xev, the insatiable love slave with an attitude; Kai, a 2,000-year-old assassin who, despite the fact that he is technically dead, is an invaluable member of the crew; and the lovestruck robot head "790."