The Casey Anthony trial may ultimately equal or even eclipse the O.J. Simpson trial, in terms of galvanizing the attention of the nation. Yet, Ms. Anthony was not an athlete or movie star when her trial began. She has no "Dream Team" of famous defense attorneys. What, then, explains the level of attention she is generating?

First, Ms. Anthony represents a brainteaser for many people--a kind of psychological Rubik's Cube. She doesn't fit their preconceptions of a killer. She's pretty. She has a nice smile. She is young. She is female. She is (and this may be unfortunate, but it is true) a white woman and a woman who is not poor. She has no history of violent crime.

Thus, people are looking extremely closely at Ms. Anthony and listening with great intensity to witnesses, her attorney and the prosecutor in this case speak about her. We want to solve the puzzle of how the person we see and about whom we hear might be able to suffocate and dispose of her own adorable daughter.

Unlike Susan Smith, the South Carolina woman convicted in 1995 of murdering her two sons, Casey Anthony offers no clues. She doesn't claim a history of mental illness as a defense. She hasn't confessed to being a killer and blamed it on the darkness that can come with severe depression.

Unlike Scott Peterson, the Modesto, California man convicted in 2005 of killing his wife Lacey and unborn child Conner, there is no lover-in-waiting to "explain" why he murdered. Peterson had met beautiful masseuse Amber Frey and seemed to have wanted a life with her, free from other commitments.

The window onto Ms. Anthony's soul is especially cloudy and draws the nation ever closer, squinting through the glass for any glimpse.

Second, Ms. Anthony, whether a killer or a mother who inexplicably did not report her daughter missing for over a month, is a conduit for buried, forgotten terrors still inside all of us. 

During childhood, we were all so vulnerable physically and emotionally, so entirely dependent on the good will of our guardians, that we suppressed the thought that we could be with a mother or father who disliked us, wished we did not exist, or might even be able to act on it. Such fears are, in childhood, unthinkable, and, in adulthood, still locked deep inside us.

Casey Anthony, the pretty, smiling, mother who may well have murdered her daughter is, in fact, every adult's worst, long-denied childhood nightmare. 

The chance to see such a woman in captivity, and to ponder what she is accused of, is like going to the zoo to see the rarest, deadliest monster you can imagine, the one resurrected from the deepest recesses of your mind in its most fragile moments. And, what's more, even if she is that monster, she may or may not be freed.

The third reason that Casey Anthony's murder trial rivets so many of us is the hardest to speak of, let alone to admit. Many, many people who experience the joys of starting families, nonetheless recall wistfully what it was like to be unencumbered. 

Raising kids is hard work, a lot of it necessarily selfless, and millions of us have thought at one moment or another, "What exactly have I gotten myself into--and why? What would my life be like if I could still just worry about myself." 

If guilty, Casey Anthony actually acted on this ambivalence, attempting to rewrite history and free herself to live the life of a single woman, not a single mother. She speaks to a dark corner of the id (instinct) inside so many of us, the part that, happily, relatively effortlessly for most every one of us, yields to the ego and superego (conscience).

These three reasons combined are like three points of a plane: They steady our gaze and serve as the perfect foundation to focus our attention. 

And consider this: If found guilty, there will almost certainly be an appeal. If found innocent, Ms. Anthony's every action will remain riveting. Freed, she could leap from the accused killer of her daughter to a reality TV star faster than you can say, "What has become of us?"

Dr. Keith Ablow is a psychiatrist and member of the Fox News Medical A-Team. Dr. Ablow can be reached at info@keithablow.com. His team of Life Coaches can be reached at lifecoach@keithablow.com.

Dr. Keith Ablow is a psychiatrist and member of the Fox News Medical A-Team.