At the end of Colm Tóibín's poignant 2009 novel "Brooklyn," Eilis Lacey leaves her native Ireland to join her husband Tony in New York. Left behind is broken-hearted Jim Farrell, with whom she had a romance and who had no idea she was secretly married.

Tóibín's new novel, "Long Island," takes place 20 years later. Eilis and Tony and their two children live in a family enclave on Long Island. In some ways, life there is not all that different from life in Enniscorthy — everyone watches; everyone knows everyone else's business.

"At times, Eilis found it stifling living beside Tony's parents and his two brothers and their families. They could almost see in through her windows."

Tony's family is a talky bunch — their Sunday dinners are four hours of yelling, and everyone discusses everyone else's business. But not with Eilis; even after 20 years with Tony, she's an outsider. Her father-in-law has never learned to pronounce her name; her mother-in-law recuses her from Sunday dinners.

When a man comes to the door and tells Eilis that his wife is pregnant by Tony, the plot is set in motion. The Italians band together. Eilis takes off alone, heading to Ireland once again— ostensibly for her mother's 80th birthday but really to escape the problem of the baby, which the man has threatened to leave on her doorstep.

In Enniscorthy, Eilis is, once again, an outsider. When they were growing up, "There was nothing special about her," her old friend Nancy thinks. "Now she stood out. She seemed like a different person. Something had happened to her in America."

Eilis can't avoid running into Jim, who manages the pub, but this time, the tables are turned — Jim is secretly engaged to Nancy. Seeing Eilis again fills him with longing and confusion. "He himself was like one of his own worst customers, someone who knew what he should not do but was driven to do it regardless, no matter how much trouble it would cause."

"Long Island" is about secrets and dreams and the conflict of desire over duty. The point of view toggles among Eilis, Jim and Nancy and, of the three, it is deeply practical Nancy who is the most determined that her dreams — of marriage to Jim and a bungalow outside of town — become reality.

Tóibín's writing is taut, with delightful flashes of humor — a wedding guest directs his dance partner around the floor "like a man driving a tractor." Eilis's fretful mother says, of a neighbor, "She died of the party. Vodka and good cheer one day and a coffin and a hearse the next. And if anyone thinks this is happening on my birthday, they can think again. I will bar the door."

Is it too late, in mid-life, to start again? Is it fair to hurt others in order to gain your heart's desire? And what if your heart desires conflicting things? Whatever you decide, these characters understand, there will be damage. "Long Island" is a wonder, rich with yearning and regret.

Laurie Hertzel also reviews books for the Washington Post and the Los Angeles Times. She is at lauriehertzel@gmail.com

Long Island

By: Colm Tóibín.

Publisher: Scribner, 304 pages, $28.