Amy Billig was born January 9, 1957, in Oyster Bay, New York, the first of two children of Nathaniel Solomon Billig, a gallery owner, and Susan Billig, an interior designer and art dealer. The Jewish family relocated to Coconut Grove, Florida, in May 1969. Described by her mother as a sociable "flower child" who played music, wrote poetry, and trained dolphins at the Miami Seaquarium, Amy attended the Adelphi Academy of Coral Gables and, lacking a car, regularly hitchhiked short distances around her neighborhood.
On the afternoon of March 5, 1974, Amy called her father to borrow money for lunch with friends and began hitchhiking to his art gallery on Commodore Plaza. She was last seen by construction workers at the corner of Poinciana Street and Main Highway. She never arrived at the gallery. After an initial delayed response from a Miami-area detective, the Miami Police Department launched an active investigation following a 6 a.m. call from her mother on March 6.
Investigators concluded Amy's disappearance was involuntary and theorized she had gotten into a vehicle with her abductor(s). The only physical evidence recovered was her Instamatic camera, found beside Florida's Turnpike near Wildwood on March 18; its film showed images of an unidentified pickup truck and a white van but yielded no further leads. Tips suggested Amy may have been abducted by members of the Outlaws or Pagans motorcycle clubs, both of which had passed through Coconut Grove en route to Daytona around the time of her disappearance. Two Outlaws members visited the Billig home in response to the family's pleas but denied holding her.
Sixteen days after the disappearance, twin brothers Charles and Lawrence Glasser, then 16, attempted to extort $30,000 from the family by falsely claiming to hold Amy; they were arrested at the Fontainebleau Hotel on March 22, 1974, and pleaded guilty to extortion.
Beginning shortly after Amy's disappearance and continuing for 21 years, an anonymous male caller who identified himself as "Johnson" repeatedly harassed and taunted Susan Billig with graphic claims about Amy's fate. In October 1995, FBI agents traced the calls to Henry Johnson Blair, a 48-year-old U.S. Customs Service employee. Blair was convicted of two counts of stalking on March 6, 1996, and sentenced to two years in prison; he denied any involvement in Amy's disappearance. Susan Billig later settled a $5 million civil lawsuit against him. A journal entry Amy wrote about a man called "Hank" six weeks before vanishing has been noted by some as a possible, unproven connection to Blair.
Other leads—including a 1976 Tulsa tip, a 1985 theory that Amy was a deceased woman named Terri Ann Warner (disproven via dental records), and a psychic consultation—did not resolve the case. Before his death in December 1997, former Pagans member Paul Branch reportedly confessed to his wife that gang members had abducted, gang-raped, and fatally drugged Amy at an Everglades clubhouse; the man he named denied involvement.
Susan Billig died on June 7, 2005, and Nathaniel Billig died in 1993, both having spent the remainder of their lives searching for their daughter. The case remains unsolved.