Marilynne Robinson isn’t ready to leave Gilead yet. The celebrated writer surprised and delighted her fans Monday night when she revealed that she is considering a fourth novel in the series that has earned her a Pulitzer Prize and two National Book Critics Circle Awards.

Robinson was at Columbia University in New York for a reading and discussion about “Lila,” the presumed final volume of her trilogy about a minister and his family in Gilead, Iowa. The evening, sponsored by the Heyman Center for the Humanities as part of its Writing Lives Series, included a public discussion with Rev. Robert Hardies, the senior minister of All Souls Unitarian Church in Washington, D.C.

Alexander Chee, a former student of Robinson’s and a visiting writer at Columbia, introduced her and then sat down to enjoy her conversation with Hardies. Chee reported via email, “It was sometime during that conversation that she said, without any warning, ‘People should be prepared to say quartet instead of trilogy.'”

The crowd of about 150 people cheered.

“She quickly clarified that she has had further thoughts about the characters,” Chee reports, “and that she felt confident that a fourth novel was likely. She would not, however, offer any further details about it publicly. After a questioner said her mom wanted more from Jack Boughton, she laughed and said she got that a lot from people.”

“Gilead,” the first novel in her series, won the 2005 Pulitzer Prize for fiction and the National Book Critics Circle Award for fiction. “Home” was a finalist for the National Book Award in 2008. “Lila” won the National Book Critics Circle Award for fiction earlier this month.