NOTE: This primer was originally published Feb. 20, but is being republished in time for the "Battlestar Galactica" two-part finale which begins March 13 as many readers may have missed it because of this site's transition to Airlock Alpha.

It seems like some fans could've used a "What the Frak?" video segment for what happened in last week's "Battlestar Galactica" episode "No Exit."

Confusion abounds across the Internet on the exposition-focused outing that revealed a lot of the backstory about the Final Five and their relationship with the Cylons created by the Twelve Colonies.

We're no experts in "Battlestar Galactica." OK, we are ... so we'll try to explain this the best way we can, because this is knowledge you're going to need to know going into March and the final episodes of the SciFi Channel series.

I'm not as witty as the "What the Frak" lady, but I am good with details.

Basically, as we already knew, humanity's birth came from a planet called Kobol. We visited that planet in the first and second seasons, and all that was there was ruins. The Twelve Tribes worshipped gods, and while it's unclear who those gods were, they did at some point create artificial life forms. When the exodus from the planet happened, the Twelve Tribes went one way, and the artificial life went another, creating a colony they called Earth.

Organic memory transfer, or as we like to simply call "downloading," had been invented by this form of "Cylon" on Kobol, and they took that technology with them to Earth. After time, however, the Cylons were able to reproduce, and with that more natural form of extinction prevention in place, organic memory transfer became a lost art.

These reproducing Cylons thrived on the planet, and pretty much forgot that they were high-tech machine based in the first place. They ended up repeating what their ancestors did (because history does have a tendency to repeat itself, and "It has happened before, and it will happen again" has been a constant mantra on "Battlestar Galactica") and they ended up creating artificial life of their own, which they may or may not have called Cylons, but we'll call them Cylons, because that just makes it easier to describe.

Those Cylons were enslaved by the "humans" on Earth, and they eventually rebelled and battled with the "humans."

During all of that, the five scientists we would come to know as the Final Five had realized that they needed to protect themselves, and had become aware of the legend behind downloading, and set out to redevelop the technology. Tyrol worked night and day on the technology, and it was something that Ellen Tigh had offered toward the end that created the breakthrough and allowed the Five to reinvent the technology.

When the bombs fell, everyone on the planet died, but the Final Five downloaded to their ship they had in orbit. And much like the ragtag fleet thousands of years later, they took off for their own destination: The Twelve Colonies.

Because they didn't have FTL drives, the trip would end up taking a couple thousand years, however that's not how much time passed on their ship thanks to Einstein and all.

They made some stops along the way, including revisiting the Temple of the FInal Five as a way to retrace the steps of the original exodus.

Their goal was to get back to the Twelve Colonies and warn the humans there that if they create artificial life, they must embrace it and not enslave it. By the time they got to the Colonies, however, it was too late, and the artificial life they had created had already revolted, and there was an all-out war.

The FInal Five arrived and instead of fighting these Centurions, they discovered the machines had a very strong religious belief in a single god. Ellen decided to use that to their advantage, to help refocus their efforts away from revenge on the humans, and into simple evolution.

She proposed to them that they could help them perfect evolution through human models and the like, and in return, they would have to end their war with the humans, which happened about 40 years before the events of "Battlestar Galactica."

The Final Five first created John Cavil in the likeness of Ellen's father. It's likely he looked old and such from the very beginning, but had the mind and maturity of a child. Cavil, however, was very intelligent, and he had a hand in creating some of the future models that would follow him.

One model, Number Seven known as Daniel, was called "artistic" and "sensitive," and Cavil felt that he was getting more attention from his Final Five creators than Cavil was. So Cavil had his line "destroyed," and we put that in quotes because it's never said what happened to Daniel's line after Cavil disrupted the cloning process, only that the results were "permanent."

Cavil was very independent and had his own ideas about things. About 20 years before the later attacks, Cavil got tired of the fact that the Final Five were not interested in seeking "justice" against the humans for enslaving his ancestors, and finally executed a plan to get that justice. He knew the Final Five would stand in his way, so he killed them by locking them in a compartment and suffocating them.

That allowed them to download, and when they did, Cavil was able to imprint new identities and wipe their memories. He would deposit them in the Twelve Colonies, to give them time to interact with the humans there, and to then be killed by the nuclear holocaust he was planning.

Cavil then reprogrammed the skin jobs and placed devices in the Centurions to keep them loyal no matter what (removing their free will) and erased all memories of the Final Five, except for the fact that the Final Five were forbidden to be discussed.

The idea was that when they downloaded back to the Hub following the holocaust, they would realize the error of their ways, in how the humans needed to be wiped out, and would beg for forgiveness.

The problem was that the Final Five didn't die in the holocaust. Some of them seemed to have received "messengers" -- similar to Head Six and Head Baltar (and maybe even Head Leoben) that warned them about what was happening, and made sure they were all in a position to survive.

They were allowed to survive, and Cavil thought this was amusing. When he would interact with them, he would torture them, or make them do things they would never do otherwise, and exact his own revenge on them continuously without them ever knowing why.

So does this make more sense? Either way, "Battlestar Galactica" airs Fridays at 10 p.m. ET on SciFi Channel.