Adam was last seen in Towanda, Kansas sometime during the late spring or summer of 1999. He lived in the Pine Ridge Mobile Home Park with his adoptive parents, Doug and Valerie Herrman. Adam had been taken from his biological parents and placed in the Herrmans' care when he was two years old, along with his two younger siblings, and the Herrmans later adopted him. He was homeschooled, and his younger siblings attended public school.

Doug and Valerie later stated Adam ran away from home during the first week of May 1999, after Valerie spanked him with a belt. They said they were afraid to report him missing because they thought they might get in trouble with the authorities for the spanking and would possibly have their other children taken away. (Adam was placed in a children's home for two days in 1996 after Valerie spanked him with a belt and caused bruises.) The Hermanns stated Adam ran away frequently and, after he disappeared in 1999, they assumed he was either homeless or with his biological parents. They continued to collect adoption subsidy payments for Adam, approximately $700 a month, until his eighteenth birthday. When they declared bankruptcy in 2002, they listed him as a dependent. They filed for divorce in 2003, and listed Adam on the divorce documents. (The divorce case was later dismissed and the Herrmans are still married.)

Adam's disappearance didn't come to police attention until late 2008, when his adoptive sister, Crystal Espinosa, contacted law enforcement with concerns about the child. She had tried to locate him through the Kansas Department of Social and Rehabilitation Services (SRS) and discovered the SRS believed he'd lived with the Herrmans until he turned eighteen, something Espinosa knew was untrue.

Adam's adoptive older brother, Justin Herrman, says his mother physically abused Adam, but he says he never saw Doug hurt the child and that sometimes Doug tried to stop Valerie from abusing him. Justin said he once called the police after Valerie threw Adam against a wall and pulled his hair, but by the time authorities arrived his mother had persuaded him to say he'd made up the story. Police have no record of this call, but other relatives corroborated Justin's abuse claims. An aunt says Adam was chained to a bathtub faucet the last time she saw him, and Valerie's mother says she abused Adam, locked him in the bathroom and forced him to sleep in the tub. Espinosa claims she saw her mother kick and hit Adam and step on him. Both of Adam's adopted siblings said he was locked in the bathroom and denied food; they occasionally sneaked in food for him. Valerie denies having mistreated Adam, though she admits she occasionally spanked him and sometimes used a belt. She claimed psychiatrists believed Adam had an attachment disorder and either bipolar disorder or schizophrenia, and that the doctors advised her to lock Adam in the bathroom at night because he had threatened to kill his parents.

After Adam's disappearance, Doug and Valerie told their family he'd been given back to the care of the state. At one point they claimed he'd been placed in a state mental hospital. Adam's biological sister, who was adopted by another family, last saw her brother in approximately 1994. A year or two later he sent a Christmas card, and this was the last contact she had with him. She says she spoke to Doug and Valerie several times after 1999 and they told her Adam was fine. Eventually they asked her not to call anymore.

The Herrmans haven't faced any charges in Adam's disappearance, but investigators have named them as suspects in his case and stated it's possible they could be charged with murder, even if Adam's remains are never found. The Herrmans could also face charges for allegedly abusing Adam before his disappearance, for failing to report him missing, and for fraudently accepting money for his care when he was no longer in their custody. Police searched their current residence and the mobile home where they lived in 1999. No human remains were found, but authorities said they'd discovered the answer to one of the questions they had. They declined to elaborate on what it was they uncovered.

The circumstances of Adam's disappearance are very murky, and investigators can find no evidence that he is still alive. His case remains unsolved.