Wealthy and devout, Michael and Julia Glynn are the envy of their neighbors and the model Irish Catholic couple, bearing Michael's increasingly painful and crippling arthritis with stoicism. In hope of a miracle, their priest suggests a family pilgrimage to Lourdes. Yet these pious holiday plans are thrown into doubt when anonymous, obscene letters begin to arrive, full of terrible accusations.

At sixty-three years old, million-dollar lottery winner PJ Halliday would be the luckiest man in Pondville, Massachusetts, if it weren’t for the tragedies of his life: the sudden death of his eldest daughter and the way his marriage fell apart after that. Since then, PJ spends both his money and his time at the bar, and he probably doesn’t have much time left—he’s had three heart attacks already. But when PJ reads the obituary of his old romantic rival, he realizes his high school sweetheart, Michelle Cobb, is finally single again.

Sybil Van Antwerp has throughout her life used letters to make sense of the world and her place in it. Most mornings, around half past ten, Sybil sits down to write letters—to her brother, to her best friend, to the president of the university who will not allow her to audit a class she desperately wants to take, to Joan Didion and Larry McMurtry to tell them what she thinks of their latest books, and to one person to whom she writes often yet never sends the letter.

A year after her child is born, Jane suffers a series of strange episodes: amnesia, premonitions, hallucinations, and an inexplicable sense of dread. Three days after her first visit to a psychiatrist, Jane suddenly goes missing. A day later she is found unconscious in Brooklyn’s Prospect Park, in the midst of what seems to be an episode of dissociative fugue; when she comes to, she has no memory of what has happened to her.

Anthony Fennell, an Irish journalist and playwright, is assigned to cover the underwater cables that carry the world’s information. The sum of human existence—words, images, transactions, memes, voices, viruses—travels through the tiny fiber-optic tubes. But sometimes the tubes break, at an unfathomable depth.