Pentilla left her home in Missoula, Montana in late September 1991. She planned to travel to San Diego, California to meet with a missionary group. Pentilla was in Las Cruces, New Mexico in mid-October 1991. She had decided to bike to Mexico and work with another mission assisting the poor. Pentilla called her mother who resided in Montana between October 1 and October 13 to report her trip's progress. She called home the last time on October 17 from Deming, New Mexico. She placed the call at a pay phone from a Shell gas station, that is no longer in operation. Pentilla was thinking of traveling to Minnesota to visit a friend. Pentilla's mother offered to pay for her transport to Minnesota or to go back home after she made more concrete plans, and Pentilla agreed to call her mother that evening with her decision. She has never been heard from again. Pentilla’s belongings were discovered by hunters under a tree about a mile off State Road 26, seven miles from Hatch, New Mexico, in 1992. There has been no trace of Pentilla since, and her bicycle has never been found.