Novelist Lisa Carey’s fifth book is set on St. Brigid’s, a remote and isolated island off Ireland’s west coast. Growing up in an Irish-American family in Brookline, Carey felt an instant connection to Ireland when she first visited after college. “It really called me,’’ she said, particularly the island of Inishbofin, where she wrote much of her first novel. The area’s hold on her apparently has not diminished much.

“St. Brigid’s isn’t a real place,’’ Carey explains; it’s inspired by Inishbofin’s sister island, which was evacuated by the government in 1960, its people having tired of living in a place without electricity, running water, or telephones (“not even a priest,’’ Carey added).

After seeing a documentary about the now-deserted island, she said, “What I immediately thought was: ‘I want to write about something horrible happening there.’ ’’ In “The Stolen Child,’’ an American woman, also named Brigid, arrives on St. Brigid’s in 1959, coming to the island to claim an inherited cottage. There she becomes entwined in the lives of two local sisters, Rose and Emer.

“I had planned to write a very realistic horror story of what happened on this island, once people turned against this American woman whom they initially had welcomed,’’ Carey said. But she found that fairies and changelings kept popping up. “I’ve always been drawn to magical realism,’’ said Carey. “I’ve been reading Irish myth and history for 20 years now. There are so many stories.’’

The novel took another unexpected turn. “I intended Emer and Brigid to be very intense friends who became enemies. While I was writing it, they became lovers,’’ Carey said. “Later, when I went to research St. Brigid, I found this whole thread of modern-day worshippers of St. Brigid as the patron saint of lesbians.’’

Carey reads 7 p.m. Saturday at Brookline Booksmith.

Kate Tuttle, a writer and editor, can be reached at kate.tuttle@gmail.com.