[5] Susan Billig had suffered four miscarriages before giving birth to Amy;[6] she later described her only daughter as a sociable, "spiritual" teenager and a "flower child", very much "into nature".

[14][15] On the afternoon of March 5, 1974, Amy returned home from school, ate a yogurt, then telephoned her father to ask if she could borrow $2 to pay for a scheduled lunch with some friends in nearby Peacock Park.

[n 2] She was observed by construction workers hitchhiking at the corner of Poinciana Street and Main Highway in Coconut Grove, close to her family home, in the early afternoon.

By 6 a.m., a frantic Susan Billig had again reported her daughter missing to the Miami Police Department; on this occasion, an investigation was launched.

[20] Flyers in both English and Spanish were also distributed both door-to-door and in public locations throughout South Florida in the hope of generating leads regarding Amy's disappearance.

[24] Her mother also contacted the Miami Police Department almost daily to inquire as to updates and progress in the investigation in addition to holding several news conferences in the hope of maintaining public interest in her daughter's disappearance.

[29][n 4] On March 16, a telephone tip from a girl who identified herself as "Susan Johnson" claimed that Amy had been abducted by the Outlaws Motorcycle Club.

[30] Shortly thereafter, a family friend telephoned the Billig residence to inform Amy's parents he had heard from a lawyer who had previously performed legal work for The Outlaws of rumors of a teenage girl recently "taken from Miami".

As the fact Amy was a vegetarian had been unreleased to the media, Susan found credibility in this particular sighting that her daughter was alive and being held against her will.

[22] Sixteen days after Amy's disappearance, her family received a phone call claiming that she had been kidnapped and was being held for a $30,000 ransom.

[31] The perpetrators of this extortion attempt proved to be 16-year-old twin brothers Charles and Lawrence Glasser,[32] who had no involvement in Amy's disappearance.

Prior to sentencing the youths, Judge William Gladstone stated the brothers had "a long way to come back from the serious delinquent and tragic events which they caused.

This individual also claimed that Amy had been abducted by members of an organized sex ring, was being held captive and that Susan herself was to suffer the same fate.

[35] In one phone call, Susan was told that her daughter had two weeks left to live; in another, he stated that he had cut off Amy's tongue.

[15] Although the harassment Susan endured from this individual ultimately caused her to suffer sleep deprivation, nausea and seizures, her forbearance in the face of this ongoing harassment to secure her daughter's release led her to continually engage in dialogue with the perpetrator in the hope the calls could be traced, the caller would reveal his identity, or that he would reveal the whereabouts of her daughter.

Several individuals claimed to recognize her daughter, with those providing information—almost all with connections to motorcycle gangs—frequently indicating Amy was in a state far from where Susan physically was at the time of these new developments.

[4] By January 1976, Susan's search had extended to Oklahoma upon receipt of a tip from a gang member named David who personally contacted her to claim to have recognized her daughter from a newspaper photograph as a girl he had previously "owned".

This individual agreed to meet with Susan at the family home, where he informed the Billigs their daughter had been extremely timid, submissive and "quiet like a mute" while in his company; he also described a distinctive scar upon Amy's body which had never been disclosed to the media.

[39][n 5] In August 1985, a 33-year-old man named Alex Courvier informed a Pennsylvania police force he had recently seen a missing persons flyer depicting Amy Billig and recognized her as a young woman named Terri Ann Warner, who had died of natural causes in Texas in the summer of 1974 and whose body had never been claimed by loved ones.

The caller was 48-year-old Henry Johnson Blair, a married father of two daughters who had worked for the United States Customs Service for twenty-four years.

[44][45] Blair admitted at trial to having obtained a form of sexual pleasure from making the hoax calls but insisted he had not intended to cause distress; he also claimed to be an alcoholic with an obsessive–compulsive disorder and thus not responsible for his actions.

[46] Six weeks prior to her disappearance, Amy is known to have written in her journal about a man she called "Hank", whom she claimed had asked her to accompany him to South America, although the entry indicates she had "told him he is crazy" in response.

Reportedly, Branch had chosen to confide the specifics of Amy's abduction and murder to his wife when informed his own death was imminent.

[44] Branch himself had been repeatedly questioned by investigators in the months and years following Amy's disappearance but had always denied any knowledge of her whereabouts; he had also personally spoken with her parents.

The numerous leads Susan Billig received regarding her daughter's disappearance ultimately led her on an unsuccessful nationwide search for Amy.

Her efforts saw her speak with death row prisoners and motorcycle gangs and pursue tangible leads in numerous states such as Washington, Oklahoma, and Nevada[52] and—as late as 1992—to travel as far afield as the United Kingdom[22][n 9] in her search for her daughter—ultimately to no avail.

Among the theories Susan speculated as to why her daughter had not initiated contact was that Amy had been intimidated by her abductor(s) and was either being held against her will or had been brainwashed.

[56] On March 8, Susan invited several friends and acquaintances who had assisted in her quest to locate Amy to a private memorial service for her daughter at her home.

Although dressed entirely in black, Susan later stated she obtained a "tremendous sense of peace" from the ceremony, adding she and her guests would now attempt to "laugh and be merry because Amy would have wanted us to."