What happened to Caylee? It was the question in the trial of Casey Anthony - a question the prosecution team was convinced the physical evidence would answer.
"The evidence is overwhelming," Florida Attorney General Pam Bondi told "48 Hours." "When you add the evidence up, piece by piece...no one else could have murdered little Caylee other than her mother."
"From the evidence you will hear in this case, there is no other conclusion," Prosecutor Linda Drane Burdick said in her opening statements.
One of the first pieces was also one of the most controversial - a foul smell which the state claimed was a clear indication of foul play.
Cindy Anthony's 911 call: "There's something wrong. I found my daughter's car today and it smells like there's been a dead body in the damn car!"
Casey's car, which had been abandoned sometime after Caylee went missing, left an impression on everyone who came in contact with it.
"George goes to retrieve car... and as they approach vehicle, an overwhelming smell is emanating from it and it's coming from the trunk," Burdick continued.
"It was an odor that could take your breath away," George Anthony told "48 Hours in 2009.
When investigators tested the air in the trunk, they discovered the presence of chloroform.
"The chloroform was shockingly high - unusually high," Dr. Arpad Vass, a forensic anthropologist, testified.
Chloroform is one of the chemicals produced when a body decomposes.
Prosecutor Jeff Ashton: Do you have an opinion as to whether there was a decomposing human body in the trunk of that car?
Prosecution witness Dr. Arpad Vass: I can find no other plausible explanation other than that to explain all the results we found.
Also found in the car's trunk: a hair, possibly belonging to Caylee.
"It has a darkened band at the root portion of the hair...and this is consistent with apparent decomposition," FBI forensic scientist Karen Lowe testified.
For Prosecutor Jeff Ashton, all the expert testimony added up to one conclusion, telling the court: "That there was a dead body in the back of Casey's car."
But Casey Anthony's defense team came to a very different conclusion.
"There is no evidence linking her to anything to do with the death of this child. Period," Defense Attorney Cheney Mason told "48 Hours."
"The prosecution had to go to novel, unvalidated science to try to get a death penalty," former defense team member Linda Kenney Baden explains. "It's the kind of science that if you went into a hospital, would never be used because it would not be considered legitimate."
"I want to talk about the forensics...and what isn't necessarily science but more like science fiction. And you'll see that throughout the course of this trial as the state reaches that level of desperation," Defense Attorney Jose Baez told the court in his opening statements.
In presenting his case, Baez questioned the analysis of the evidence and in some cases, the evidence itself. "It's a fantasy of forensics, is what it is," he said.
The smell: "She threw the garbage in the trunk of her car. ...She forgot to throw out the trash. ...That's where the smell comes from," Baez continued.
The hair supposedly confirming Caylee's death:
Defense Attorney Jose Baez: That one hair is still something that you cannot say came from a dead person.
Prosecution witness Karen Lowe, FBI Trace Evidence Examiner: I can't say absolutely that that's the reason the characteristics are present. Correct.
"The hair banding is novel science. It's hardly ever been used," Kenney Baden explained to "48 Hours."
The analysis of the air in Casey's car was especially dubious, according to the defense.
Defense witness Dr. Kenneth Furton, Professor of Chemistry/Biochemistry: There's not sufficiently reliable scientific method to be able to identify the presence or absence of human remains.
Defense Attorney Jose Baez: Where can you find chloroform?
Dr. Kenneth Furton: It's pretty much everywhere. It's a very common chemical in low quantities.
But there was one piece of evidence that seemed impossible to dispute. Found in the woods just blocks from her home: the skeleton of Caylee Anthony.
"Examination of that scene revealed that the body of Caylee Anthony had been wrapped in a Winnie the Pooh blanket, stuffed into multiple garbage bags [Casey winces] shoved into a laundry bag and thrown into a littered swamp like she was just another piece of trash," Prosecutor Linda Drane Burdick told the court.
The details of the crime scene shocked the entire courtroom:
Prosecution witness Dr. Gary Utz, Orange County Chief Deputy Medical Examiner: You're looking at a human skull...
Dr. Jan Garavaglia, Chief Medical Examiner, Orange-Osceola Counties: It's tossed in a field to rot in bags...
Dr. John Schultz, University of Florida professor: Being dragged away by an animals or animals ... the trunk of the body with the pelvis and the lower legs more than likely was dragged to this area.
But most shocking of all was a strip of duct tape found loosely attached to the skull.
Dr. Jan Garavaglia: There is no child that should have duct tape on its face when it dies. There's no reason to put duct tape on the face after they die. Based on our experience, we've seen that in cases of homicide.
The prosecution claimed the duct tape was used to suffocate Caylee.
Prosecutor Jeff Ashton: Would the single piece of tape, if applied in the position shown on the video, have been sufficient to have covered the nose and mouth and make breathing impossible.
Michael Warren, Forensic anthropologist: Yes.
But because neither Casey nor Caylee's DNA was found on the duct tape....
Dr. Werner Spitz, Forensic pathologist: If the duct tape was attached on the face there would be DNA from her face on the duct tape.
...the defense countered with another theory.
Dr. Spitz: I think the duct tape was later - later event.
Defense Attorney: After decomposition?
Dr. Spitz: After decomposition. ...This duct tape was perhaps placed there to hold the lower jaw in place.
And the defense questioned the motives of Roy Kronk, the meter reader who first discovered the skull.
Defense: "You were joking, you say, about finding this body?
Roy Kronk: No, we were joking about the money, sir. I never joked about finding the body, sir. That's not what I said.
Asked if she was bothered by Kronk's testimony, Kenney Baden tells Troy Roberts, "Well, it's clear that - that he somehow moved the physical evidence."
Defense: "Is it your testimony that you put that stick in the eye socket of this skull and picked it up to be sure what it was?
Roy Kronk Yes sir - I apologize for doing so, but I did not know what it was.
Defense: And then you put it back?
Roy Kronk: Yes, sir.
There was one theory the defense didn't address: its own theory that Caylee drowned.
"The defense doesn't have to prove its case," Kenney Baden explained. "All they have to do is raise a reasonable doubt by showing there was a possibility that she drowned."
After a parade of forensic experts testified, neither side could definitively explain exactly how Caylee died. But the jury would have other evidence to consider in reaching their verdict... the behavior of Casey Anthony.
According to Florida Attorney General Pam Bondi, "It's what she did in the month after...little Caylee went missing that is the most compelling evidences of all."