D'Anna knows who the Secret Four Cylons are. And she's not telling. She's a narrative wild card. She wasn't part of the alliance negotiated between the Colonials and the rebel Cylons. She came late to this game, and she's setting new rules. And because she has leverage and uses it, the situation quickly becomes a standoff that threatens to spin out of control.

D'Anna holds the Colonials, including the President Roslin, hostage aboard the basestar. She makes an announcement: She will hold the hostages until the Secret Four are turned over to her. But this creates a real problem for Admiral Adama and President Lee Adama. They don't even know who these four Cylons are. The only ways this stalemate can possibly end is either in bloodshed or with the secret Cylons turning themselves in.

Now let me quote myself from my review of the second-season BSG episode "Sacrifice": "At this point in my movie- and TV-viewing life, I'm almost willing to say that any pitch that can be summarized as 'hostage situation' should be thrown out by whomever is potentially producing it." Good thing I used the word "almost" in that sentence, or else I'd have to eat those words. "Revelations" is the most riveting hostage standoff in recent memory. Old conventions can be made to work in your favor if there are real stakes involved. And the stakes here couldn't be bigger: Lives of major characters hang precariously in the balance, as does the secret surrounding Earth.

And because this is a BSG hiatus launcher, there's no telling what will happen or where the story might end up. The season-ending cliffhanger used to make me groan because it was an obligatory cliche. But BSG has for me single-handedly revitalized the cliffhanger with its track record of shocking unpredictability. The suspense level is amped up in "Revelations" in part simply because I knew it was a midseason finale.

One interesting point worth pondering: D'Anna says four Cylons are in the fleet. Not five. Does that mean the final Cylon is not in the fleet? Is the final Cylon a character on the basestar? Or is D'Anna lying?

When D'Anna makes the rules of the game clear, it creates a real nail-biter. She knows who the secret Cylons are. They know who they are. And we know who they are. But all the other characters must play this deadly chess game in the dark. Immediately, the secret players start quietly jockeying for position. Tory, the other wild card here, craftily gets herself aboard the basestar by offering to take Roslin her medication. Tigh tries to stop it, but he can't without giving himself away. (Once aboard the basestar, Tory swiftly burns her bridges. When the president tries to reason with her, Tory's response is: "I'm done taking orders from you.")

Tigh immediately becomes the key player here, because he's in Adama's inner circle as the rules of engagement are being established. It puts Tigh in the bind of all binds. The screws continue to tighten and options diminish: D'Anna proves she means business and airlocks a hostage, promising more will follow. (There's an inspired extreme long shot where a tiny body goes flying across the screen amid the fleet.) It could be that in this chess game, the only way to ward off the disaster is if Tigh outs himself. Watching this unfold is deliciously excruciating.

Meanwhile, Tigh, Anders, and Tyrol try to figure out how they might know the way to Earth. Supposedly they do know, but they have no more information about Earth, until...

The radio static and musical signals return in the minds of the Secret Four, like at the nebula in "Crossroads." They are drawn to Kara's Viper. They don't know why. So they must solve the mystery before the hostage situation explodes. To buy time, Tigh marches into Adama's quarters, where he...

In one of the most edge-of-seat scenes on this series, Tigh confesses everything he knows to Adama. "I am a Cylon." Adama tries to explain it away, using all the facts that we as viewers would ourselves use to debunk this belief. It's a fruitless endeavor. Tigh knows he's a Cylon. And with this knowledge he puts himself forward as the most possible valuable leverage to use against D'Anna. It's brilliant. It's selfless. It could very well cost him his life. And it's 100 percent Saul Tigh.

The ensuing Adama emotional nuclear explosion that occurs is a raw and heartbreaking performance by Olmos. It depicts nothing short of utter devastation. This man has a breaking point, and we've passed it and then some. Tigh's outing turns Adama's world upside down. Not only is Adama's best friend of 30 years a Cylon, and not only has every military decision Adama ever made now the punch line of a cruel cosmic joke, but now Adama has to put Tigh in an airlock and use him as currency. "I can't kill the bastard," Adama sobs to Lee. He literally cannot do it. So Lee steps up to address the crisis in his father's stead.

On the macro tier of the story, the brilliance of "Revelations" is how fate assembles a big picture from the jigsaw puzzle of all the characters in order to not simply point the way to Earth, but force the humans and Cylons to do it together. In addition to the Secret Four, this puzzle can only come together with the involvement of Resurrected Kara and her Viper (which begins receiving a mysterious signal, and is the only piece of equipment that does so); the renegade Cylons; and even Baltar, who reasons with D'Anna long enough to cause a crucial delay. And, of course, a higher power to make all of these coincidences play in perfect concert. Sure, this is all a construction of clever writers, placing the available pieces where they best make sense. But it's done well and done organically, and the spell of the story is never broken.

Ultimately, Tigh is in an airlock with Lee's finger on the button, who demands D'Anna stand down -- and it doesn't look like she will. I honestly didn't know whether Tigh would live or die -- I really didn't. Airlocking Cally in "The Ties That Bind" made possible this scene's palpable sense that anything could happen. It generates unbearable suspense, even while making use of that old standby: crosscutting back and forth to a character who's desperately running through hallways with crucial information to stop something awful from happening.

And how awesome is Saul Tigh? He has no regrets whatsoever about his choices here. He stands up straight and prepares to face death like the man he always has been. As the moment is drawn out, Tigh looks straight at Lee and says, "What are you waiting for, Apollo? Do it." It's a great line that elevates this character (and Michael Hogan, who plays him) into a stratosphere of awesomeness.

But Kara's word of her discovery stops everything at the last possible moment. As quickly as the crisis seemed headed beyond the point of no return, it's completely defused. She has found a signal leading back to Earth. Lee negotiates a halt to hostilities with a Yes We Can speech; everyone can go to Earth together. In a way, for this brief moment, Earth has saved everyone.

I must also admit I was blindsided by the idea that once this agreement is reached, we are going to Earth right now. I really didn't see it coming. I expected another clue to Earth, not the full solution. Again, it's a testament to this series defying expectations. The moment of truth has arrived, Earth is in reach -- and yet here's a character kernel not to be overlooked: Adama is still deflated, his spirit crushed. It takes Roslin to lift him back up.

But we're not kidding around. We're going to Earth! We get it all: the spine-tingling epic sweep, the dramatic musical score, the shot of the fleet in orbit of a blue planet, Adama making a grand fleet-wide announcement, characters celebrating and hugging. Nice stuff. Even nicer: Tigh sits alone with a bottle. Even Earth is not going to solve all our characters' problems. And then...

There's that doozy of a final shot of a devastated Earth. Adama picks up that first handful of dirt, and a Geiger counter clicks away. In addition to the implications of this scene, I must praise the technical skill. It's a tour de force of stage direction that gathers all the characters in a single, wordless tracking shot. I could easily write another 500 words on just this shot and how it breaks down all the characters and silently, implicitly comments on all of them. But why do that? You get the picture, and can form ideas of your own. One thing is certain: The dejection is palpable.

What happened to Earth, what does it mean, and what do we do now? This ending is not a cliffhanger; it's another brilliant, giant question mark -- the biggest one yet on this series. If there's a major statement being made here, above all else, it's that there is no quick fix in the Battlestar universe. For this extended journey, the destination, and all hope, has resided on Earth. Now they have found it. But apparently finding it has resolved nothing.

Earth may have allowed the Cylons and Colonials to come together, but now they are here, and they are going to have to deal with each other. Earth is not going to save these people. They will have to save themselves.

Somehow. I don't know how.

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