Rachel Lucille Cyriacks

Rachel Lucille Cyriacks was a 30-year-old mother of three living in Woonsocket, a small town in Sanborn County, South Dakota. Her marriage to Brad Cyriacks, an on-and-off relationship spanning roughly eleven years, was troubled: in August 2013 she filed for a temporary protection order in Sanborn County, citing domestic abuse, and according to family members she planned to divorce him and rebuild her life. On October 31, 2013 — Rachel's thirtieth birthday — Brad Cyriacks was arrested following a domestic assault incident and jailed in Huron. At the time, Rachel's children were staying with family members while she worked on her recovery from substance abuse.

On November 13, 2013, Rachel drove her gray-and-black 1995 Chevrolet Silverado pickup from Woonsocket to Huron, about a twenty-minute drive, to pick up her husband as he was released from the regional jail. Cell phone records confirmed her trip that day, according to investigators. Brad Cyriacks told authorities that after a brief stop at home, Rachel dropped him off at a friend's house in Huron and drove away. She has never been seen or heard from since. November 13 was her mother's birthday, a day Rachel would normally have called; when the call never came and days passed without contact, her mother grew alarmed and reported her missing in early December 2013. A green, pink and white quilt Rachel cherished disappeared from her home around the same time she did.

Weeks after the disappearance — reported variously as December 2013 to early 2014 — Rachel's pickup was found behind a building on a bee farm near Huron owned by the family of an acquaintance. The truck was inoperable, with its drivetrain removed and severe damage to the undercarriage. Brad Cyriacks and the property owner said the truck was there for repairs, but investigators noted inconsistencies in their explanations, according to Forum News Service reporting. DNA testing of the vehicle produced nothing conclusive. Over the following years, the South Dakota Division of Criminal Investigation and local agencies searched extensively: ground-penetrating radar near Wolsey, cadaver dogs, aerial surveillance, dive teams with side-scan sonar in the James River and other waters, and checks of some twenty wells, junkyards and abandoned buildings. No trace of Rachel has been found, and authorities have said they believe she is deceased.

In a 2021 interview, DCI Agent Tyler Neuharth publicly identified Brad Cyriacks as the prime suspect, saying, "Brad is the prime subject right now. He knows that, I've told him as such." Brad Cyriacks has not been charged in connection with Rachel's disappearance and, when contacted by reporters, has declined to discuss the case; according to The Daily Beast, he refused a polygraph examination. In 2016 he was convicted of violating a protection order and served time before his release in 2017. Around the tenth anniversary of the disappearance in November 2023, renewed appeals generated new tips, and investigators searched multiple locations and recovered items for analysis. In December 2023, Attorney General Marty Jackley announced a reward of up to $25,000, funded through the U.S. Department of Justice's Equitable Sharing Program, for information leading to the arrest and conviction of those responsible. The case remains open with the South Dakota DCI, which asks anyone with information to call 605-773-3331.