In the late 1980s Elizabeth Clare Prophet's dictations from the ascended masters warned that the world was entering a period of acute karmic danger, including the possibility of Soviet nuclear attack, and the Church Universal and Triumphant answered with the largest private civil defence effort in American history. At the Royal Teton Ranch in Montana's Paradise Valley, members built a network of underground shelters provisioned for years, the greatest of them designed for hundreds of people, and church families across the world sold homes and moved to Montana to be near them.
In March 1990, the period of highest danger in the prophecies, thousands gathered and many spent nights underground; the date passed without catastrophe, and the church afterwards taught that the prayer vigil had helped avert it. The episode carried costs. Fuel stored for the shelters leaked into the valley's groundwater, drawing federal and state action, and in 1989 the leader's husband Edward Francis pleaded guilty in a scheme to buy weapons under a false name, a case the church survived but never outlived in the press.
Membership declined through the 1990s, Prophet announced her Alzheimer's diagnosis in 1998 and died in 2009, and the movement decentralised. Scholars, notably in a 1994 study organised with the church's cooperation, treat the shelter cycle as a rare modern case of a prophecy heavy movement negotiating an unfulfilled date without collapse.