I've seen a lot of debate about whether the ruined planet at the end of Revelations is Earth or not, and what sort of Earth it is supposed to be. There is further debate as to whether the beach is supposed to be in Brooklyn.

With the shocking confirmation that the final Cylon is not anybody in the Last Supper photo our choices are far more limited, short of this being an out and out lie. While I don't put it past the producer of a show to lie (or certainly to equivocate) on a show's central mystery when asked a direct question, this is fairly direct. It's either a lie or a bizarre equivocation where "people" is taken to literally mean "non-Cylon" so that he's saying "The final Cylon isn't any of the non-Cylons in the picture" -- a tautology.

Let's examine the choices left to us. It's made more narrow by the declaration by D'Anna that the Final Cylon is not with the fleet. But there are no minor characters of note that are not with the fleet when she says this, other than dead characters. Worse, there are some dead characters she should not yet know to be dead. The one exception is Seelix, who is only marginally a character of note.

I've said for some time that the unmasking of the final Cylon, as a major climax of the series, must be dramatic. It has to be shocking and unexpected to most. While Baltar, who was my choice up to this point, would not have been shocking, I expected the "why" to be the real source of surprise, rather than the person. This may have to go doubly for the dead character.

Popular minor character choices Gaeta, Dee, Zarkek, Lampkin and Cottle are clearly with the fleet. And they're also quite uninteresting choices. Revealing it is one of them will elicit a "ho-hum" rather than a "Holy Shit" the way Tigh's unmasking shocked most of the audience (though of course not yours truly.) So even though some feel that D'Anna could be playing tricks by saying there are only 4 with the fleet, I see no reason for her to know that one is special, unless that one is on the base ship or dead. In fact, nobody on the fleet except the 4 themselves knows that one is special. And indeed, no reason for it to be any minor character on the fleet.

Other limiting clues include the following:

• A report that the final Cylon was chosen during the first season. Other reports suggest it was a person from the miniseries but this is less confirmed.
• Confirmed reports that there are clues in the show about this person
• The prophecy of the first Hybrid about final Cylon: "And the fifth, still in shadow, will claw toward the light, hungering for redemption that will only come in the howl of terrible suffering."
• The famous line that "Adama is a Cylon" given by Leoben, while in captivity.
• While far from certain, there are a lot of dramatic reasons to suggest D'Anna's "You, forgive me, I had no idea" is to the final Cylon, somebody singled out for special recognition in the circle.

While it's not confirmed, it is my belief that the "Final Five" plot, with a whole new class of ancient Cylons, was not fully fleshed out until the 3rd season. However, many of these choices require this plot to have been worked out in the first season when the Cylon was picked. My intuition could be wrong here.

It should be noted, that by and large there are no actual clues that point towards any of these characters (or any other characters not eliminated by the photo.) In fact, truth be known only a few of the eliminated characters (Baltar, Roslin, Starbuck and perhaps the Adamas) had actual clues, clues on the order of Tyrol's compulsion to find the Temple or his superior response to vacuum.

Joseph Adama

My former favourite was recently eliminated by a declaration by Moore that it will not be somebody the audience has not seen, not a guest star.

Note that Lampkin tells Lee Adama that he looks just like his grandfather. It would be an interesting twist if Lee were a new incarnation of Joseph, however since Lee is in the last supper photo, that doesn't work out.

I'm proud to say my prediction from last week about a ruined Earth was largely spot on. The one unresolved part was the question of whether this planet is inhabitable (and inhabited) or not. The scene with the Geiger counter suggested they wanted to tell us it has too much radiation for humans at least, but it could have several meanings.

Our current weapons could not make the whole planet radioactive, but future weapons could. There are plants (and air) and casting calls for extras suggest they may even find tribes of people on Earth.

Recent previews for this week's episode -- some minor spoilers for early in the episode here -- reveal D'Anna going to the fleet to tell them she wants the four Cylons, whom she says she has been in contact with. She says that because the revealed 4 are in the room, listening to her.

A few things are confusing me about the plot right now. "Sine Qua Non" has some seemingly highly contrived and out of character scenes to bring about certain plot movements (Adama on own, Lee as President, Saul as Commander) so I hope the payoff is worth it.

But today I want to consider two bigger pictures. For some time I've been puzzling over why the final five are sleepers. Indeed, even though they are no longer fully sleepers, they don't yet know anything more. I'm also wondering what the point of the quest plot has been.

The big confirmation in Faith was the line from the Hybrid: "The missing 3 will give you the 5 from the home of the 13th." While there is still some potential in the minds of some viewers that the 13th will turn out to be something other than the "13th tribe" this seems to confirm what other clues have been saying for quite some time in the show: The Final Five are from Earth.

While this was not news to readers of this blog, I did find it a bit interesting that she referred to the "home of the 13th" because it remains my contention that there never was a 13th tribe. That "the 13th tribe" is really a mythologized name for the people of the homeworld, who never were a tribe, per se. But since the scrolls wish to hide the true story and the origin of the Kobolians, the authors gave them the name of a tribe and a story. And indeed, since the 12 tribes all have names from the Earth zodiac, and the supposed 13th tribe "left" for Earth 2,000 years before the exodus from Kobol, this makes a lot of sense. If the 13th tribe existed and had a name, it is not from the zodiac (No, Ophiuchus doesn't count) and it's really the first tribe. But you can't call them that without leaking the truth.

However, the Hybrid's use of "the 13th" suggests perhaps more reality for this tribe. It's possible there was a tribe of Kobolians who did a return expedition to Earth, though I am not quite sure what that explains in the plot. We could have the Final Five being from Earth in several ways. They could have originated in a repopulated Earth, for example.

However, the plot that makes the most sense has the Final Five originating on the real Earth, some time in the not too distant future, and playing a part in the 3 cycles of human/AI war, exodus and resettlement.

In fact, while I did not suggest it seriously at first, I considered it a cute plot point to suggest the Final Five were in fact once ordinary humans who came of age in the late 20th century and then uploaded into machine form some time in the 21st. And as 20th century humans, they could have found that "All Along the Watchtower" was a favourite song of the group, and thus programmed it to be the "wakeup song" used when it is time to make sleeper copies of themselves, planted among the regular humans, become aware of what they are.

As I've often discussed, many clues show the Final Five to be over 4,000 years old. We see them in hooded robes in the 2,000 year old Kobol Opera House in visions, and they are almost surely the 5 priests who built the "Temple of Five" 4,000 years ago on the way from Earth.

The nature of the final five is going to be perhaps the central theme of this final season. Perhaps the most interesting thing we've learned is that the 7 Cylons are "programmed not to think of them." This has been hinted at before, but it's become much more dramatic of late.

The original Cylons (the 7 humanoids and the metallic ones) first defined the concept of Cylon in this version of BSG. Now the writers call them the Significant 7 or S7. The audience has been introduced to the concept of the "Final 5" Cylons. Because they are both called Cylons, I often see people confusing the two, and making some very wrong assumptions about the final 5. These are two very different types of Cylon, with two very different agendas. More different than any two factions of humanity in history, so it's hard to get a grasp of it.