A 4-year-old girl goes missing from her bedroom, and her well-to-do parents and two nannies fall under suspicion. Then, nine days later, the girl's decomposing body is discovered in her own bed, even though the home supposedly has been sealed off by police.
The state prosecutor first declares the death a homicide, but stokes confusion by saying that the child, who suffered developmental disabilities, may have asphyxiated by accident. After he releases the suspects, political opponents clamor for his ouster.
Never mind Mexico's raging drug war, last weekend's powerful earthquake on the U.S. border or an economy that continues to sputter. The mystery of what happened to little Paulette Gebara Farah, reported missing March 22 and found dead in her family's apartment more than a week later, is the tale that has thoroughly captivated Mexicans.
The drama is both whodunit and who-screwed-it-up-so-badly, with all the suspenseful elements of a TV crime show and Mexico's troubled criminal-justice system smack in the bull's-eye of the controversy.
The parents, businessman Mauricio Gebara and attorney Lisette Farah, received lots of support when they appeared on television to report that Paulette had disappeared after she was put to bed in their apartment in Interlomas, a suburb of Mexico City, on March 21. Supporters publicized the case through Twitter and Facebook and on billboards along some of Mexico City's biggest avenues.
The parents and the two nannies were subsequently placed under a kind of house arrest in a hotel outside Mexico City while police investigated.
Then came a most startling twist: On March 31, as investigators reconstructed events in the high-rise apartment, they found Paulette's body under blankets at the foot of the bed, where a wooden base extended beyond the mattress.
The discovery ignited a flurry of water-cooler speculation and Internet chatter: How could the girl's body have gone undetected by the parents, nannies, investigators and countless others who traipsed through the home? Was it planted there? If so, by whom?
Moreover, will anybody believe authorities if they claim to have solved the mystery?
For more than two weeks, the case has dominated television, radio and the newspapers, reduced by revved-up Mexican media to one word: Paulette. It is hard to remember a recent case that has so caught the public attention.
Each day's news brings new salacious tidbits, even if they're not always confirmed. Suggestions of marital infidelity. Armchair analyses about the apparent lack of emotion from the mother, Farah (including speculation that she may have grown tired of caring for Paulette, who could not walk well or speak).
There have been reports of jaw-dropping investigative lapses, and details of the not-so-happy lives of some of Mexico's privileged citizens.
Adding to the spectacle, pretty much everyone involved in the case, including the two nannies, has gone on-air with accounts that don't always match.
Paulette's parents have publicly set upon each other in dueling broadcast interviews with conflicting versions of the circumstances when they reportedly last saw the girl. Farah has even accused her husband of "hiding something." Gebara's family, meanwhile, has taken custody of the couple's other daughter, Lisette, who is 7.
The messier the case has gotten, the more Mexico is enthralled.
"There is nothing that compares in ratings, readership, hits on the Web and social networks that compares with the Paulette story," columnist Ciro Gomez Leyva wrote Thursday in the daily Milenio newspaper. "What has made it such a box-office success?"
Gomez suggested that Mexicans are no longer shocked by the nation's rising violence, which has left more than 18,000 people dead in a 3-year-old drug war that features beheadings and frequent gun battles between troops and cartel men.
"That is the daily landscape," Gomez wrote. "The 4-year-old girl is, instead, extraordinary."
Whatever the reason, the case has fed talk shows and Internet chatter with theorizing, amateur psychoanalysis and, inevitably, talk of conspiracy.
Commentators have dissected the conduct of the parents, with some straining to find ties between Gebara and the attorney general of Mexico state, Alberto Bazbaz, that might offer possible protection from prosecution.
The case has also taken on political meaning. Politicians with Mexico state's two opposition parties, the conservative National Action Party and left-leaning Democratic Revolution Party, are taking aim at Bazbaz's handling of the case and, by extension, the competence of the state's ruling Institutional Revolutionary Party, or PRI.
Bazbaz's boss, Gov. Enrique Pena Nieto, is widely considered the front-runner for president in 2012 and the case could prove an embarrassment for his administration. Mindful of growing public dismay, Mexico state authorities invited FBI agents to help them Friday as they examined the apartment once more.
On Saturday, Mexican news websites reported that Farah was being questioned anew by state investigators.
Though Mexican news media, and many viewers and readers, continue to hang on every new wrinkle in the case, there are signs that some people have had quite enough, thank you.
One Twitter user wrote of the saturation coverage: "Turn the page already."
Daniel Hernandez and Cecilia Sanchez of The Times' Mexico City Bureau contributed to this report.