“Learn how you can make a difference!” the flyer said.

Joan called home to say that she’d be grabbing a bite to eat downtown.

In August, Joan held a rummage sale to finance her upcoming trip to Central America with the Human Rights Advocacy and Earthquake Relief Group. She planned to assist disaster victims as well as accompany human rights activists and family members of the disappeared.

“You see,” she told her friend Mary, who had dropped by just in time to help Joan arrange small, seldom-used appliances on a card table in the driveway, “if U.S. citizens hang around with these people, they’re less likely to get kidnapped and tortured, because nobody wants to get in trouble with Uncle Sam.”

“Sounds kind of dangerous,” Mary said.

Joan shrugged and stuck a tag on an electric bun warmer. “So’s crossing the street,” she said. She reached for a popcorn popper. “But I’d appreciate it if you wouldn’t say anything to Charlie and the girls. I haven’t told them about it yet.”

Mary looked around the yard, which was strewn with makeshift tables full of household goods. She noted a set of gleaming wrenches spread around a tabletop sign that read All Metric Sizes. On another table she recognized Charlie’s heirloom collection of decoy ducks. “Where is Charlie?” Mary asked.

“In Des Moines,” Joan said. “He’ll be back on Sunday.”

They nabbed her on the plane in Cedar Rapids, a Saturday evening flight to Houston, with connections to Guatemala City and San Salvador. She was easy to spot, in her Bangladesh dress, the colorful quetzal bag perched on her lap. (Travel light, the Human Rights Advocacy and Earthquake Relief Group had advised her. Dress comfortably.) Airport Security turned her over to Charlie, who was waiting in the terminal.