The reason Battlestar's fourth season has worked so well thus far is because there's a larger purpose driving it -- an unapologetic, fully committed serialized format that assumes you watch every week. In past seasons, the show occasionally tried to deliver somewhat more stand-alone stories (and one could argue that led to some of the series' weaker outings, like "Black Market," "Hero," "The Passage," or "A Day in the Life"), but with the series' end date etched in stone, all pretense for increased audience accessibility has been jettisoned, and the show has committed to telling the stories that advance its larger purpose.

Now, having said that, it's worth noting that although the larger overarching story is driving this series, there's still plenty of room for episodes that more prominently feature certain characters and themes over others. For example, "The Road Less Traveled" emphasized military protocol, "Faith" emphasized religion, "Guess What's Coming to Dinner?" emphasized the characters' roles in a cosmic mythology, and now "Sine Qua Non's" emphasis is government and leadership.

This episode takes the fallout from "Dinner" and turns the focus primarily into a story about the operations of the Colonial government in the absence of President Roslin, and how it functions alongside the military (which is to say, dysfunctionally). Completely absent are any scenes that feature Roslin or the other characters on board the Cylon basestar that jumped away; their fate is a mystery left for next week. I admire the strategy of this season, which is that being away from some characters' stories simply means spending more time on the equally compelling affairs of others -- in this case, for the entire episode. (There's been a sense of unrelenting momentum this season, where the story moves along and the writers ask us to fill in the blanks of what was off-screen and implied. I'm of the opinion that the approach has worked.)

Renegade Six is rushed to sickbay where she dies on the operating table -- an ominous sign for any hopes of the tenuous alliance that had existed. Meanwhile, there's chaos aboard Colonial One, where the Quorum tries to separate facts from rumors about Roslin's disappearance; the frenzy has real-world disaster recognizability as a situation where emotion awaits further news and in the meantime feeds upon itself.

Also made clear in the early scenes is the sense that business must and will go on, both in the government and on Galactica. Adama and Tigh start planning contingencies (with almost too much calm) for what to do if indeed all those Vipers are now gone. And if Roslin is missing and perhaps dead, the government must continue to function, and Vice President Tom Zarek intends to step up and do the job -- that is until it's made clear (and this happens very quickly) that Admiral Adama has absolutely no intention of recognizing a Zarek Administration.

Zarek is frankly pissed that he may have to step aside simply because Adama doesn't trust him. But he has no choice. Lee has an apt military phrase for the situation: "Facts on the ground." The civilian government cannot function without Adama's approval, and Adama does not approve of Tom Zarek. Period. It makes you wonder where this fleet would be if Roslin and Adama were not able to coexist as a (usually) unified front.

So Lee convinces Zarek to step aside while Lee chairs a search committee to replace him. I'm honestly not sure whether this is prudent or patently absurd. The president is gone, the government is about to grind to a halt, Adama is rejecting the legitimate administration -- and Lee turns to the sort of deliberate bureaucracy that typifies a real government, as opposed to the contrived one that actually exists. Hey, I don't have a better idea, and Lee's plan seems about as level-headed as any. But given how dire the situation is, it just seems so ... calm. Calm to the point of madness.

Lee recruits a reluctant Romo Lampkin (Mark Sheppard, reprising his popular character from last season) to aid in the search. Lampkin sees the case as a high-risk, low-reward endeavor that won't get him much of anything in return. What did he get in return for defending Baltar, you ask? He got a "room with a view"; his quarters feature a hilariously tiny 6-by-6-inch window, apparently much coveted. He also gets plenty of headaches from people who hate him for getting Baltar acquitted.

The question becomes, who exudes all the qualities of a real leader and will be acceptable to the Quorum and to Admiral Adama? Lee and Romo spend a good deal of time debating the merits of leadership (with Romo offering up little tidbits of wisdom like the fact that those who show no apparent ambition actually have more of it than anyone else; it's just hidden from view), while crossing names of a dry-erase board. The details of this process are enjoyable, but at the same time there's a certain telegraphed inevitability to it. When Romo starts writing down names that will work rather than crossing off those that won't, he only comes up with one name, and it's not a groundbreaking shock when the camera reveals that it's -- gasp -- Lee Adama! I will admit that it is, however, an interesting wrinkle to the larger plot. It's also proof that BSG is not afraid of moving the plot ahead at lightning speed; Lee is sworn in as president before the episode ends.

But I'm not quite sure what to make of the scene where Lampkin reveals this epiphany to Lee. He points a gun at Lee and seems prepared to pull the trigger, which is so downright unexpected and played for suspense value that I'm inclined to say it simply comes out of left field. Lee has some good speechmaking in this scene, but I couldn't help but be distracted by how forced it felt for Lampkin to suddenly become so unhinged. What causes this? We learn that his enemies killed his cat weeks ago, and apparently that's his final straw. But, wait -- we had seen the cat jumping around in earlier scenes. Oh, that was just subjective-POV, Romo-imagined narrative trickery. Personally, I don't think this story needed Romo's cat playing Bruce Willis in The Sixth Sense.

It also feels forced because Romo has always been the coolest of all customers -- a dry and cynical con man who knows human nature better than anybody. Watching him melt down here doesn't play to the strengths of the character or the actor; it seems at odds with Lampkin's persona, and I didn't quite buy it. It's too much platitude and not enough truthful characterization.

Significantly more truthful characterization takes place in the Adama/Tigh stories aboard Galactica. There are some great scenes here. Take, for example, the one where Adama calls Sharon in to answer for killing Renegade Six. He wants an explanation. She supplies one. To call it insufficient is an understatement. Adama is pissed -- and I mean pissed -- over Sharon's reckless act. You can always count on an angry Adama being worth some meaty drama, and it doesn't disappoint here. Sharon has essentially destroyed her relationship with Adama -- and her standing on the ship -- because of fears inspired by her visions, and it lands her back in the brig.

Meanwhile, this episode finally turns back to the relationship between Tigh and Caprica Six. A lot has transpired off-screen since "Escape Velocity"; you can see in their body language that their relationship has greatly evolved. She calls him "Saul." Their relationship is obviously complicated, with a dose of both codependence and distrust, and Tigh still sees Ellen when he looks at her. I love how this scene invites us to fill in blanks and imagine how things between them have changed gradually over time; there's an economy to the narrative that makes it seem like so much more has happened than we've actually witnessed.

The real heart of the story, though, is Adama's. Roslin is missing, and Adama is determined to find her. When the president's Raptor is discovered along with a dead pilot, and Galactica investigates and subsequently finds a destroyed Cylon basestar, there's every reason to believe the president and Galactica's Viper detachment are dead. But Adama can't accept it. He goes into personal-feelings-indulged mode, very much like the search for Kara in first season's "You Can't Go Home Again." He begins to lose objectivity. He sends resources out on fruitless missions. He delays preparations for getting the fleet under way. At one point, even Lampkin makes a point about it: "I always imagined you a realist, admiral, not one to indulge a vain hope at the cost of lives. But then, everyone has his limits."

Then there's the revelation that Caprica Six is pregnant by Tigh's doing. I didn't see that one coming. Let's completely set aside for now the whole issue of this potentially being the first fully Cylon child; the Adama/Tigh scene where this is revealed is terrific. Once again, a pissed Adama is an endlessly watchable Adama, and the result is a dramatically charged stand-off that gets you pumped up for the intensity of the drama even while it makes you wince about seeing these two old friends cursing and finally coming to blows with each other. I especially recoiled when Adama brought Ellen's name into it; if only he knew what Tigh literally sees in Six. The brawl gives way to the perfect bit of levity after Adama's model ship is destroyed: "You know how many times I've had to repair this thing?"

Slowly but surely, this story becomes the tale of these two old guys and their situations involving women: Quite simply, what are they gonna do? For Adama, the situation grows in poignancy as we realize, if we hadn't always realized, that he loves Roslin. And amid his loss of objectivity over trying to deal with this fact, he realizes he must turn command of Galactica over to Tigh, with orders to continue the search for Earth. Adama intends to wait alone in a Raptor for Roslin to make an improbable rendezvous.

The Adama/Tigh friendship, with all its history, is so poignant that you dread the day when the other shoe drops and Adama finds out he's a Cylon. At this point, this question is more about Adama than about Tigh. It isn't even an issue in the story's mind that Tigh, a secret Cylon, is given command of the fleet. Tigh is simply Tigh, working through his many issues, and that's all there is to it. He intends to carry out Adama's orders.

"Why are you doing this?" Lee asks Adama. "Because I can't live without her," Adama responds. Boom -- the emotional truth of the episode right there. And Adama waits, by himself, in empty space, alone. Hope springs eternal. When it comes to Laura Roslin, Adama can't afford to be objective. Sine qua non: Without which there is nothing.

Footnote: The number 47 once again shows up in the dialog here, in reference to names being crossed off a list. The whole insertion-of-47-into-scripts phenomenon, dating back to TNG, has persisted throughout BSG's run. Rumor has it Joe Menosky was the one responsible for encouraging this behavior. I felt compelled to ask Menosky about it, and he confirmed his complicity in this conspiracy, and pointed me to this page and this page to demonstrate the uncanny significance of 47.

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