The following contains MAJOR SPOILERS for "Revelations," the 10th episode of Season 4 of "Battlestar Galactica."

Somehow the final five became the final four, and Earth isn?t all it?s cracked up to be.

In "Revelations," the "mid-season finale" of the final and fourth season of "Battlestar Galactica," there are indeed many revelations.

Revived Cylon Deanna (Lucy Lawless) is awake and in control. She has human hostages on the Cylon mother ship, including President Roslyn (Mary McDonnell). She uses her knowledge that four of the final five are on Galactica, four crucial to leading the way to Earth. The Cylons want to find Earth as much as the humans do. Deanna kills a human hostage and threatens to kill more if the four cylons don?t reveal themselves and lead the way to Earth.

Tory (Rekha Sharma) is the first to embrace her Cylonhood and volunteer to join the Cylons, not revealing herself immediately. She volunteers to go to the Cylon ship to give Roslyn her medicine. Once she gets there, she tells Roslyn that she is one of the final four Cylons, and that she will no longer take orders from her.

The three remaining closeted cylons find they are drawn to a particular viper on Galactica -- one that also has the interest of Kara (Katee Sackhoff). All four don?t know why, but there is something about the viper that is different, and they need to figure it out.

In the meantime, Tigh (Michael Hogan) is experiencing guilt over the death of the first hostage. As Deanna threatens to kill more, he is faced with the inevitable dilemma of either coming out as a Cylon or allowing more people to die if he remains silent. He chooses to do the former, revealing to Adama (Edward James Olmos) that he is one of the four Cylons.

Adama is so traumatized by the revelation that he has a nervous breakdown and stops functioning at the time when he is most needed to decide what Galactica should do -- about the hostage situation, about the Cylons, and about finding Earth.

Tigh suggests that if Adama threatens to flush him out of the airlock, Deanna will back down. He also offers to reveal who the other Cylons are.

Tigh is arrested and brought to the airlock. Shortly afterward, Tyrol (Aaron Douglas) and Anders (Michael Trucco) are also arrested and brought to the airlock. The four have been revealed, and with Adama drunk and incoherent, and Roslyn held hostage on the Cylon ship, it?s up to Acting President Lee Adama (Jamie Bamber) to decide what to do.

He first works to get his father out of the near catatonia he is in, reversing the roles they once played some time back, and demanding he to pull it together. Then he goes to order to send Tigh out the airlock, making sure he gets a good bloody slug in the face in first.

As Lee is about to send Tigh out the airlock, Kara realizes why the viper is so important. The three Cylons had all been drawn to it because it had the crucial information that would lead them to Earth. She discovers the coordinates to Earth on the viper, and races to stop Lee from killing Tigh, saying to Lee ?Call it what you want, but whatever higher power it is wants us to find Earth with the Cylons.?
Lee and Deanna meet, and come to an agreement to work together to get to Earth. Deanna releases the crew. The humans and Cylons go to Earth together.

What they find when they get to Earth has both humans and Cylons horrified. Whatever civilizations were there, whether in Earth's ancient past, or our future, it's all been destroyed. The ground is radioactive, and whatever is left of a civilization has been obliterated.

So, what now?

What Worked

It was exciting to see the four sleeper Cylons reveal themselves (or be revealed), and all the reactions and consequences of those revelations. Adama?s reaction was the most extreme, but it was a reaction we should have expected of a man whose closest friend of thirty years reveals himself to be ?the enemy.?

Tory?s defiance of Roslyn was not altogether unexpected, either. Of the four, she seemed like the one most ready to accept that she was a Cylon. Her loyalties clearly weakened over the course of the half-season -- or at least, her ambivalence was evident.

Perhaps the most poignant reaction was that of Anders, who looked to Kara for some sort of assurance that she might still accept him, only to have her completely ignore him. Talk about heartbreak!

What Didn?t Work

Two things that bothered me were: (1) Deanna knows who the fifth Cylon is. Why hasn?t she revealed what she knows? (2) The trip to Earth seemed kind of anti-climactic. I know the sudden change of venue was necessary to move the story along, but it seemed a bit too rushed. They were in space limbo, and then suddenly they were on dead Earth. It was kind of a jarring change.

Regarding the fifth Cylon, I, as is the case for everyone, can only speculate as to who it is and why Deanna doesn?t just come out with it. It?s either someone on Galactica who is still unaware of his/her "Cylonity;" it?s someone who IS aware, but is staying silent about it, either for devious reasons or self-preservation; or it?s someone who isn?t on Galactica at all. Could Deanna be keeping it secret to throw off the humans? Could she be afraid of who it is?

We?ll have to wait till some of us become nearly ancient to find out.

Giving Credit Where Credit Is Due

"Revelations" was written by Ronald D. Moore, Bradley Thompson, and David Weddle, and directed by Michael Rymer. "Battlestar Galactica" airs on the SciFi Channel.

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