(CNN) -- One year ago, a sheriff's dispatcher in Orange County, near Orlando, Florida, received a strange 911 call. A small child was missing -- and had been for a month.
Casey Anthony didn't tell anyone that her daughter, Caylee, was missing for 30 days.
The child's grandmother was frantic, talking a mile a minute. But her mother seemed unemotional, disconnected from the drama around her.
So began the Caylee Anthony case, a mystery that became a nightly fixture on cable television and captivated true-crime buffs across the country.
Today, the child's 23-year-old mother, Casey Anthony, is in jail, charged with first-degree murder, and faces the death penalty if convicted. She denies harming her daughter or having anything to do with her disappearance.
Her attorney, Jose Baez, has said that once all the facts are known, it will become clear that his client is innocent.
While reports of missing children are not unusual -- a Haleigh and a Haylee are two recent examples -- several elements came together in the Caylee case to make it a high-profile news story, said Robert Thompson, who heads the Bleier Center for Television and Popular Culture at Syracuse University.
"The fact that it's a toddler had that really dramatic, 'this is our worst nightmare' thing. It doesn't get any more dramatic than that," he said. "Then, of course, there's Casey herself."
The 30-day delay in reporting Caylee's disappearance, along with the frequent release of police documents containing the personal details of the family's life, whetted the public's appetite. See how the case unfolded »
"By that time, it becomes self-fulfilling," Thompson said. "Once the story gets into the inbox of places that cover this thing -- Dateline, America's Most Wanted, Greta van Susteren, Nancy Grace, Geraldo -- it becomes a packaged drama. We want to know how it turns out."
Caylee's body was found December 11, six months after she disappeared and just a few blocks from her grandparents' house. The remains were bagged and partially buried in a swampy, vacant lot.
Duct tape covered the child's mouth. But the cause of Caylee's death is just one of many questions that remain unanswered a year later. And the answers are not likely to come soon, if at all. Casey Anthony's trial, originally scheduled to begin October 12, has been pushed back until some time next year.
Thousands of pages of court files have been made public. Police questioned Anthony's friends and boyfriends, pored through her cell phone records, went through her computer, and seized her digital photo albums. They even analyzed her sleep patterns. But the picture that emerges is far from clear.
The story begins at about 9:40 p.m. on the evening of July 15, 2008, with Cindy Anthony's call to 911. The call capped a day in which she and her husband, George, a retired police officer from Ohio, received an impound notice and tracked down their daughter's abandoned white 1998 Pontiac Sunbird -- and then their daughter, Caylee's mother, who was staying with a boyfriend.
"I found out my granddaughter has been taken," Cindy Anthony told the 911 dispatcher. "She has been missing for a month. Her mother finally admitted that she's been missing. ... We're talking about a 3-year-old little girl!"
"I need to find her," Cindy Anthony continued. "I told you my daughter was missing for a month. I just found her today, but I can't find my granddaughter. She just admitted to me that she's been trying to find her herself. 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."
George Anthony told police later that the car gave him "a bad vibe."
"I got within three feet of it. I could smell something. You look up and you say, please don't let this be. Please don't let this be," he said in a July 24 police interview.
A cadaver dog confirmed for police the scent of human decomposition in the car trunk. Casey Anthony's friends told police she said she hit an animal with the car. But many of her stories did not check out, investigators said.
Although Casey Anthony has frequently fallen out with her parents, they have always insisted that she is innocent. They haven't visited her in jail for months, in part because authorities record the visits and release them to the public.
During the search for Caylee, some say Casey Anthony didn't behave the way one would expect of a worried mother. She went to nightclubs and sent hundreds of text messages to friends, according to cell phone and text transcripts and investigative reports released by police.
Those phone and text records also showed that she hardly mentioned her missing daughter.
At one point, police analyzed her sleep patterns, finding that the cell phone calls and text messaging ceased for only three or four hours a night at about the time Caylee disappeared.
For weeks, curiosity seekers camped out in lawn chairs outside the Anthony home, where the family had posted large flyers asking, "Where is Caylee?" When the crowd grew unruly, Cindy Anthony waved a hammer and George Anthony shouted back at the hecklers.
Authorities say they also found traces of chloroform, a knock-out drug, in the trunk of Casey Anthony's car. And they said that on her computer, they found Internet searches of missing children and chloroform Web sites.
Investigators first labeled Casey Anthony a person of interest, and later, a suspect. She was indicted on a charge of first-degree murder on October 14.
But Thompson, the pop culture professor at Syracuse, cautions that the final curtain hasn't fallen on this drama.
"It isn't necessarily a slam dunk," he said. "We have the JonBenet Ramsey case to show that we may think one thing, and it isn't so." Early in that investigation, authorities said John and Patsy Ramsey were "under an umbrella of suspicion" in their daughter's death, but they later were cleared.
"These things are capable of twisting around," Thompson said. "But that's another element that makes them interesting."