In Lionel Shriver’s novel “The Mandibles,” it’s 2029, the United States has defaulted on its loans, and the country is plunging into an economic abyss. Suddenly, a cabbage costs thirty-eight dollars. Savings accumulated over a lifetime evaporate in an hour. Former hedge-fund managers compete for jobs as waiters. (Their new patrons are foreigners; America, like other failed states, has become a magnet for tourists who can afford luxuries that the natives can only dream of.) Everyone is grimy, because water shortages have rendered showers brief and infrequent. This is made particularly troublesome by another post-apocalyptic issue: there’s not enough toilet paper.

“I found that really gratifying,” Shriver said, as she considered her prescience, one recent afternoon in London. Since the lockdown went into effect, she has been sequestered with her husband, Jeff Williams, at their row house in Bermondsey. It is a modest, comfortable place, decorated with thrift-store finds and small ceramic sculptures—smooth, faceless figures—that Shriver made, along with memorabilia that Williams has gathered in his decades as a jazz drummer. But Shriver was not feeling cozy. “Truth is, I’ve never been this shaken,” she told me. She wasn’t worried about getting sick. “The virus doesn’t faze me,” she said. She was afraid that she would prove oracular about more than toilet paper, and that we are hurtling toward global financial cataclysm—what she described in “The Mandibles” as “an ongoing, borderless nightmare ended only by death.”