Here's a session in the box that's intense enough, deep enough, psychological enough, and acted well enough that I'm willing to say it could be compared to some of the top-shelf box sessions from Homicide, which of course is the undisputed champion of the box.

Because this is Battlestar Galactica, however, there are additional considerations, like debate over religion and sci-fi concepts, the mysterious mythology of Kobol, the warfare between civilizations, and the characters' self-granted right to torture the subject who is in the box. It's a brave new world.

A Cylon copy of Leoben Conoy (Callum Keith Rennie), whom Adama killed in the miniseries, is discovered hiding on a ship in the fleet and is immediately taken into custody. Adama recommends dispatching this Cylon at once, lest he cause damage to the fleet or start putting dangerous ideas into people's heads. Roslin, however, wants Leoben interrogated for information about the Cylons. Adama puts Kara in charge of the interrogation with a warning that Leoben is a master of psychological manipulation, and that he will try to get into her head.

Thus begins a duel of wills between the interrogator and her subject. The interrogation takes up most of the episode's running time, but the show is not confined to the interrogation room like Homicide's famous "Three Men and Adena." This episode cannot be fairly held up to the likes of "Three Men and Adena," but it's worth noting that it made me think of that episode on more than one instance.

This interrogation is not about guilt or innocence. That Leoben is a Cylon is beyond dispute. He fully admits it. He's guilty of being a Cylon, and so far in this universe, there is no innocent Cylon; they are all the enemy. (One wonders what will happen once Sharon is revealed as a Cylon.) No, this is about learning about the Cylons and their tactics, something that will hopefully garner strategic knowledge.

The thing about Starbuck as played by Katee Sackhoff is that she's believable balancing the no-nonsense intensity with the abrasive sarcasm. She can pull off the role of badass, but at the same time she has a condescending grin that reminds me of Garak's philosophy of adversarial encounters: When in doubt, smile, because it confounds your enemy.

It does not, however, confound Leoben, who immediately claims to have planted a nuclear warhead somewhere in the fleet -- a claim that cleverly narrows the scope of the interrogation's information-gathering goal. Not that it matters, because Leoben's refusal to answer questions quickly turns the interrogation into a battle of wills and a discussion of Leoben's existence as a human mimic.

For example, Leoben admits to being hungry, having not eaten in days. Starbuck asks him, what's the point of being a machine programmed to feel hungry? Wouldn't that simply interfere with the efficiency of operation? For that matter, why feel pain? That's a question for when the beatings and torture begin. Can Leoben, who is a machine, flip a switch and turn off the pain? And if he does so, does that make him less "human"? Starbuck's assertion is that it would: Human beings are forced to suffer through their pain, and if a Cylon can simply turn their pain off, they really aren't human.

But Leoben either cannot or refuses to turn off his pain, and takes his beatings -- followed by being repeatedly dunked into a bucket of water -- as if it were his duty.

Between the torture are discussions that venture into philosophy. Leoben says he sees "patterns" in the universe that humans cannot see, which he claims gives him the ability of prescience. Furthermore, he says "I am God," and says that all Cylons are gods in a way, because they have a foresight that humanity can't grasp. More specifically, in an iteration of a speech Leoben gave Adama in the miniseries, he says the Cylons were created by God as a punishment for humanity's sins.

Callum Keith Rennie's performance as Leoben is effective in its straightforwardness. Here's a Cylon whose goal under duress is to turn the screws of mental manipulation, to be menacing via his utter Cylon implacability, and yet at the same time he maintains an underlying sincerity, as if he believes every word he says to Starbuck (which he very well might). The claim of the nuclear warhead, we suspect all along, is simply the device by which Leoben buys himself time to start in on his Cylon philosophizing.

There's a lot of meat in "Flesh and Bone." In addition to Leoben's pervasive dialog, there's also the interesting underlying religious themes, including the polytheism versus monotheism in the difference between the Colonial Lords of Kobol versus the Cylons' singular God. What does all of this mean? I don't know that it means anything specifically right now, except to suggest the nature of the Cylons having established their own independent religion and their belief that they have souls of their own. Can a machine have a "soul"? (Starbuck's initial belief is that Leoben has software, not a soul, but she begins to question that belief.) Perhaps one way to look at it is that any being intelligent enough to comprehend its own death and ponder its meaning probably has the right to lay claim to the concept of a soul.

What's interesting is how this process wears on Starbuck, the interrogator. Leoben eventually is able to get into her head by telling her things about herself that seem too personal to have been researched in a background check. Leoben either has unique insights, or is a master of psychological manipulation. Eventually, he begins prognosticating, saying that humanity and the Cylons are involved in a cosmic, historic struggle destined to repeat itself. He quotes from Colonial religious scripture (either that, or The Matrix Reloaded), saying, "All of this has happened before, and all of it will happen again." He tells Starbuck that the Galactica is going to find Kobol.

Beyond the prognostication, the simple fact is that Starbuck beings empathizing with her subject. When Leoben refuses to give up information, she calls his willingness to endure more torture a malfunction, a state of sickness. Eventually, she can't stomach it anymore. The more Leoben talks, the more questions Kara has, and the more troubled she becomes. Sackhoff shows a solid range in her character's gradual shift from hard-line interrogator to one of surprising vulnerability. One of the show's best strengths is its moral ambiguity; by the end Kara is praying for Leoben's soul, if he has one.

Kara isn't the only one empathizing in this story. There's also Sharon on Caprica, who meets with her fellow Cylons to report that she's had sex with Helo. "Does he love you?" Six asks. The Cylons tell Sharon to convince Helo to stay on Caprica, or to kill him. This puts Sharon at a crossroads, where she chooses Helo over her co-conspirators, and decides to truly go on the run with him rather than pretending.

Meanwhile, the other Sharon on the Galactica reaches the end of her frustration. Her humming and stroking of the captured Cylon Raider (ever-so-eerie, that) raises Tyrol's eyebrow a bit, to the point that Sharon wants to clear herself of being a Cylon once and for all. She visits Baltar in the lab and insists on being the first test subject for his Cylon detector. When he demurs, she plays the "you owe me" card, reminding him that she and Helo saved him from annihilation on Caprica. I like the continuity of this moment, which reminds us how all these players have been moved into place.

The scene where Baltar analyzes the results and is about to inform Sharon is a mini-masterpiece of hypnotic tone and dialog. Baltar realizes Sharon is a Cylon, and then must decide what to say to her. Six tells him Sharon's likely to go into Cylon mode and break his neck on the spot. Can't have that. I liked the musical continuity, melding what I'm willing to call Six's theme and Sharon's theme (see the opening minutes of "Water") into a tense undercurrent. Sharon stares at Baltar, awaiting his answer, as if unconsciously waiting to explode. Below the tension is the humor of Baltar's panicked facial expressions, as he looks back and forth and decides what to say. Of course he says what he must to protect himself from possible death, and tells her that she's 100 percent human. Of course, the implications arising from Baltar's discovery have their own foreboding.

Back in Leoben's storyline, Roslin orders the interrogation ceased and promises to spare Leoben's life if he tells her where the warhead is. Ironically, Leoben comments -- in regard to being tortured -- that the military are trained to dehumanize people, even as the interrogation itself had forced Kara into doing exactly the opposite. He confesses what we suspected all along -- there is no warhead. But then he whispers to Roslin that "Adama is a Cylon." Roslin has her own response: "Put him out the airlock." Which they do.

This is some pretty dark stuff. Interestingly, the character arc for Roslin in the episode is the opposite of Kara's. Roslin begins the episode in a vulnerable place, having prescient dreams involving Leoben, and waking up in particularly rough shape from her illness. By the end, she shows a side that I didn't know existed, willingly venting a man into space without a trial or hearing. Because he's a Cylon, he has no rights, is guilty and is given an automatic death sentence. End of story. It raises some tough questions, to say the least. That the story doesn't compromise or supply easy answers is a credit to its makers.

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