Two universes coexist in the same place, in the same space, at the same time. The Light Universe is home to the League of 20,000 Planets, brought to Order by His Divine Shadow after the millennia-long Insect Wars. The Dark Zone is the ancestral home of the Brunnen-G, who defeated the Insects some time after migrating to the Light Universe to escape their dying sun.

The Lexx passes from the Light Universe to the Dark Zone and back a couple of times via a fractal core during its journeys. The story begins in the first season with the Light Universe and progresses with escape into the Dark Zone, and back to the Light Universe in search of protoblood, which keeps Kai animated. From there the Lexx travels across the Light Universe throughout season two until it is forced to withdraw back into the Dark Zone, where it stays throughout seasons three and four.

The Dark Zone contains Brunnis, the ancestral home of the Brunnen-G, Fire and Water from season three, and Earth from season four. Key characters from the Dark Zone include Poet Man, Prince, May, Priest, and Vlad.

The Light Universe contains the Cluster, which is His Shadow's ruling seat over the League of 20,000 Planets, the Ostral-B heretics, and a number of worlds and space vessels/establishments that the Lexx encounters. Key characters from the Light Universe include His Shadow, Thodin, Bog, Yottskry, and Brizon.

Key characters who show up in both universes are Stanley Tweedle, Kai, Zev Bellringer, Xev Bellringer, 790, Giggerota (Queen, Genevive), Lyekka, Mantrid, (Schlemmi) Fifi, (Laleen) Bunny, Moss, Lomea, (Wozzard) Dr. Ernst Longbore, and the Time Prophet. (More information on reincarnated characters at Lexx Wiki.)

“Time as you know had a beginning and time has an end and then time begins again. As we shall each live our lives again exactly as before, I have been gifted to see into the old cycles of time. Not very clearly mind you, but I have learned that in the future-past the Brunnen-G, the great victor in the war against the insect civilisation, shall be destroyed at the hand of His Shadow. But after His Shadow leaves the Cluster they will be destroyed at the hands of the Brunnen-G. This has happened before and it will happen again.” — The Time Prophet

That was a pretty awesome bit of pinpoint prophecy, and adds more questions to the time philosophy. If she can see all times as 'now', then she has a remarkable and probably overwhelming gift. More interesting, she seems to be timeless herself, since we see her being accessed for advice also by Kai and His Shadow. There is no mention of how this happens or where she resides, but she seems to be outside of time itself. We don't know if people must enter a hypnotic or dream state to reach her and we have no clue if she's part of a religion, but we do find out in season four that Vlad kills her. Maybe... From the Lexx Wiki.

• Vlad's older form is played by Anna Cameron, the same actress that played the Time Prophet. It is unknown if this is intended to suggest that Vlad may have been produced from the remains of the Time Prophet, in the same way that the assassin Kai was produced from the original Brunnen-G warrior.
• Though Vlad is believed to have killed the time prophet, this could be interpreted as the time-prophet's death being used in the creation of Vlad.
• Actually, Vlad herself states that she travelled to see the Time Prophet, who revealed to her that she would find Kai on Earth eventually. Vlad then states that she killed the Time Prophet.

I find it extremely interesting that the Time Prophet focuses on such a narrow part of prophecy when so much other stuff happens, and you could argue that much of this becomes self fulfilling prophecy, and even make the leap to reading between the lines to see that these prophecies may have been subtly aimed at Zev, as though she were a kind of subtext catalyst, because she is Kai's motivator on several occasions since Kai cannot motivate himself, being undead without a will.

Before I go deeper, let's do a quick review. There are several things that HAD to happen in order for all the rest to happen.

Oddly, the very first thing that happens is Kai exposes his people to His Shadow's planet killer (we learn this in season two's Brigadoom), then throws himself right at His Shadow's feet in a kamikaze attempt to kill him. That right there creates the perfect feedback loop for becoming the last of the Brunnen-G in the prophecy. If the Time Prophet had never told him, would he have done this?

The next big thing that went precisely perfectly wrong before the prophecy could be fulfilled was Stanley Tweedle slapping Thodin's bug bomb and causing it to become damaged. Because the bug bomb was damaged, it detonated the wrong cable and the cluster lizards were set free.

Because the cluster lizards roamed freely, Zev's attendant robot during her sentencing was destroyed by a cluster lizard, which also accidentally knocked the lever that activated the lusticon she was strapped to. That resulted in not only killing the cluster lizard, but shoving some of its tissue into the lusticon just before it engaged, resulting in Zev's love slave transformation incorporating cluster lizard DNA into hers, effectively creating a hybrid. That made her strong enough to pull free of her straps. Then she shoved the robot head left over from the savaged attendant robot into the final phase of the lusticon's brainwashing program, accidentally creating a robot head that would obey her every command.

Meanwhile, everything going wrong with software and equipment malfunctions meant that Thodin was inadvertently brought back to the sentencing chamber, where he freed his gang and a cannibal named Giggerota.

After that the catalyst became a Zev/790 combo unlocking doors and fleeing through the judicial compound to the special projects area with Stanley Tweedle, where they met Thodin and his crew of Ostral-B heretics intent on stealing the Lexx.

Because everything was going out of control, His Shadow activated Kai, last of the Brunnen-G who was bioengineered into an undead assassin, which was the final variable in an equation of everything going perfectly wrong.

Chances are, Thodin would never have succeeded in stealing the Lexx even if his original plan had gone perfectly. Because everything went WRONG, the most powerful weapon of destruction in the two universes was swiped by a prisoner with a low grade security guard job, a love slave, a robot head, a cannibal, and a dead guy. None of them had a clue what they were doing and what was really going on. They had no plan to execute and no one to help them. They ultimately go on to fulfill the prophecy.

Kai could have done none of this by himself, obviously.

Onward. And back to the spiral symbol on the Time Prophet's hat. Headpiece. Whatever. This is a Lorenz attractor and if you want to know more you can click it to go to the wikipedia page it came from.

Lexx fans have pretty big discussions about the Cycles of Time and everything beginning again and happening again. The following is a very well summarized look at the typical thoughts that pop into people's heads as they watch Lexx, from the Lexx Wiki.

"What is not certain is how the interaction of the two universes affects the cycles of time as the Light Zone, after its Big Crunch, will presumably experience another Big Bang, resulting in a new universe. This could be considered to be a new cycle of time, but would not be a synchronised event with the Dark Zone, meaning events could not play out exactly as before. If the cycles of time are independent of the interactions of the two universes, then it is unclear when or how the cycles of time end and begin again.

Another trail of thought is that the Light Zone cannot enter a big bang phase until the Dark Zone has collapsed. In such a case, both universes could theoretically begin at the same time, despite their endings being at different points in time."

This is a real conundrum. Let me propose something different. Quantum chaos theory notes that something looping over and over will eventually go off course just because initial conditions aren't precisely met the same way at the beginning of each new loop. Because something is very slightly off, there is very slight change over many loops. Eventually something might change enough to be noticeable, but only if you skip across all the loops in between when you look at it. I think the Time Prophet's inability to see clearly into the cycles of time could plausibly be blamed on quantum chaos.

Over a great deal of loops you wind up with a different pattern going on that might not look like the original loop at all (although in the Time Cycles philosophy there doesn't seem to be an original because time has been looping forever). I think this solves the next conundrum of the two universes getting out of synch. They may have originally looped together, but after all the big stuff that happens around the Lexx, this becomes impossible. If the loop synch becomes broken, can it even keep looping any more? What if the Cycles of Time could be broken into becoming a straight line that is no longer affected by all the loops that came before it? 

Another thing that grabs my attention is His Shadow's obsession with Order. I'm sure the writers didn't intend this level of content analysis, but it would be very easy to plug bifurcation theory into the Cycles of Time and the time loops suddenly behaving very differently. Bifurcation theory notes that although a change might be very small, it could throw a dynamic system into a completely different trajectory or history of events. This is the straw that broke the camel's back, if you will. Or as Xev tells Prince in season three, the Lexx is not just a tiny grain of sand that will tip the balance in the war between Fire and Water, but a whole desert of sand.

Case in point. Mantrid escapes his prison world and eventually collapses the Light Universe ~because~ the Lexx showed up in his life. If the Lexx had never traveled to Mantrid, the Light Universe would never have collapsed. That is the tiny change (very tiny in two whole universes) that completely tipped the Cycles of Time over from repeating, in my opinion. I don't think it's possible for them to repeat any more because there is no more reset back to the original starting point. This particular cycle of time that we are watching is the last of the repeating cycles. That's why THIS cycle of time is so important. These tiny little changes that added up over the cycles finally reach a climax level where just one more change breaks the ordered dynamic system down into chaos.

His Shadow was obsessed with Order. Just saying. It's interesting that he created the very thing that brought about his demise. Actually, plans for the Lexx were stolen from the Ostral-B heretics to begin with, so whoever came up with the plans to bioengineer a weaponized space bug in the first place is the original grain of sand that would eventually foil the Cycles of Time. Because the only way out of the complete human genocide that His Shadow had planned was to tip the world upside down and break it apart. I'm sure they had no idea what was coming.

If you've not seen Lexx or perhaps hadn't gotten to season four yet, or maybe just never thought about it that much, Earth is in the Dark Zone, in the same universe the Brunnen-G originated in many thousands of years before. If we do a little simple math, we can work our way backward and add up the 4000 years of stasis in the cryopods while the Lexx drifted, and the 5000 year gap where the Time Prophet spoke to the Brunnen-G citizen about Stan finding Kai in the Memory Catacombs, that is 9000 years. We also know Kai had been dead for 2000 years by the time they all met on the Lexx, and Brunnis 2 had been settled for awhile already before His Shadow blew it up, so Brunnis 2 was blown up 4000 + 2000 = 6000 years before Lexx arrived to Earth, and 3000 years before that Kai's people were still on Brunnis 1. Kai's people migrated from the Dark Zone to the Light Universe at least 7000 to 8000 years ago. Who knows how many times this had happened in the Cycles of Time before the Light Universe collapsed. I don't think Lexx was a part of the Cycles of Time for many, many loops. Incremental changes.

If you don't like the quantum chaos theories flattening out the Cycles of Time, I have another plausible explanation for why the Time Prophet couldn't see very clearly into future past. According to holographic principal, what we think is the world around us is really a projection from a different dimensional location. Viewing future past events would be like looking into projected reflections. This can create an illusion of Cycles of Time when you see repeating reflections (this trick can be done with mirrors facing one another, or a camera taking a picture of you holding a picture of it in a mirror, you can really mangle your brain on this). Instead of events happening over and over exactly the same as before, as she says, they happen only once but are reflected to infinity, so it ~looks~ like time loops repeat themselves. In that case, the Cycles of Time are an illusion, but the Time Prophet still has the really cool gift of seeing all times as now.

And if you don't like the Cycles of Time dissolving into illusion, just hold that thought, because I'm still working on a way that time looping could hold water in fiction fizzix. 

I was probably still going more places with this, but it's gotten really long and I'm worn out. Time to move on.