Sadie Zimmer had answered the door. She knew who Polly Childs was, of course, though they had never officially met. “Yes?”

“Just wondering,” Polly said, “if you’re planning on renting your home this summer. I have clients who would pay ten thousand dollars a week for it in August.”

Sadie had given Polly a tired, barely tolerant smile. “Not renting,” she said, and she closed the door in Polly’s face.

Later people reported sightings of Sadie Zimmer at Alley’s General Store and the up-island Cronig’s. Christine Velman saw Sadie driving out to her parents’ house in Katama—and in conversation a few days later during the meeting of the Excellent Point book group, Lydia Phelps confirmed that Sadie was remaining on the Vineyard for the summer, although she was taking a break from the pie business. Reed had moved out, Lydia told Christine, although whether he was off island or still on the Vineyard was unknown. Most of us guessed he was off island—and, as we know, off island is a very big place.

But then, late on the evening of the Fourth of July, Ken Doll nearly ran over a bicyclist on South Road. Thankfully Ken Doll caught a flash of reflective gear and swerved out of the way. But the incident flustered Ken Doll. Who goes biking at eleven o’clock at night? he wondered. He was only on the road himself because he had to retrieve his teenage daughter, Justine, from a party at Lucy Vincent. He put the window down to shout a warning at the biker—but when he saw it was Dr. Reed Zimmer he was so surprised that he hit the gas instead. He had heard that Dr. Zimmer had left the island for good.

But no. Reed Zimmer was still on the Vineyard, living in nearly hermetic seclusion at Sheep Crossing in a house owned by his medical-school roommate’s elderly aunt Dot, who let the house sit vacant except on the rare occasions when the medical-school roommate used it himself. The medical-school roommate, Dr. Carter Mayne, worked as the head of the infectious diseases department at the Cleveland Clinic, a demanding job that left him precious little vacation time, so when Reed called saying he had marital problems and asking whether he could use the house for the summer, Carter said, Of course, man, it’s yours. The key is under the mat. I’ll let the caretaker know. Carter refused Reed’s offer of fair-market rent, because if anyone understood marital problems it was Dr. Carter Mayne. He was on wife number 3, and he was about to leave her for a nurse in the burn unit.

Carter’s aunt’s cottage is nothing special, but Reed doesn’t want, nor does he deserve, anything special. Every minute of every day since Sadie caught him at Lucy Vincent with Harper has been excruciating.

Reed fell out of love with Sadie all at once, a year and a half earlier: it was as if someone had thrown a switch from IN LOVE to NOT IN LOVE. This had happened in the dark days of January during a blizzard. Reed and Sadie had been trapped at home as the snow piled up outside. Sadie had built a fire and put a short-rib-and-onion pot pie in the oven; she had opened a bottle of red wine and turned up Harry Connick Jr. on the stereo. She patted the seat next to her on the sofa and said, “Come sit with me.” Reed dutifully sat, and she handed him a wineglass, which he accepted, despite the fact that he rarely drank, and when he did—that is, if there was no chance he would be called into work—he preferred beer or a Scotch. They had clinked glasses, and Sadie said, “Kiss me.”

Reed could remember feeling repulsed. He had not wanted to kiss his wife. He had not been charmed or lulled by the cozy wintertime domesticity. He could see where things were headed: Sadie would want him to make love to her, and he simply didn’t want to. He took a sip of his wine, hoping alcohol might work its magic, might make him feel something for the woman next to him. It was nothing short of deliverance when, a second later, the house phone rang: Reed was needed at the hospital.

Reed had thought of himself as saved. Spared.

But Reed wasn’t a quitter. He was thoughtful and methodical by nature. He figured that if the switch could be turned off, then it could also be turned back on.

The night of the blizzard he had been called upon to deliver a baby—Dr. Vandermeer, the OB, was stuck in Woods Hole—and Reed, who had not been in a delivery room since his ob-gyn rotation in medical school, found the experience enormously gratifying. The patient was a first-time mother, Alison, who had been determined to give birth without drugs, but the baby was big, and it was a struggle. Alison was swearing and screaming; the agony on her face troubled Reed, and he almost encouraged her to give in—at least take some Nubain—but in the end he was glad he didn’t. Alison handled each contraction like a mountain she had to summit, and Reed and the two labor-and-delivery nurses cheered the way they might have for an elite athlete—Michael Phelps or Lindsey Vonn. After four hours of fight and nearly fifty minutes of pushing, Spencer Douglas entered the world weighing nearly nine pounds, a beautiful, healthy baby boy.

When Reed and Sadie reunited post-blizzard, nearly thirty-six hours later, Reed described the birth to Sadie. He detailed Alison’s determination, the focus in her eyes, the strength of her will, the raw power of a female when she was in the midst of her most profound and fascinating function: giving birth. Reed had been a doctor for more than twenty years by that point, but he had still been struck by the nobility of it.

He had grasped Sadie by the shoulders. “We should have a baby.”

“What?” she said.

“Why not?” Reed said. Since the birth of Spencer Douglas, Reed had cottoned to the idea of having a child. Children, as Reed understood it, often saved marriages.

But at the mere suggestion of having a child, it seemed that Sadie’s own switch had flipped to the off position. It wasn’t just that she dismissed the idea, it was that she was viscerally offended by it. She had believed them to be of a single, childless mind. Reed’s change of heart was a betrayal. Sadie slept in the guest room that night. But then, a few days later, Reed found her back in their bed, and he thought she had come to her senses. However, when he tried to crawl in, she’d stopped him.

“I shouldn’t be the one sleeping down the hall,” she said. “You should.”

And so for the year and a half that followed, Reed had been sleeping alone. Not only did Sadie not sleep alongside him, she also wouldn’t touch him at all. She avoided his hands when he passed over the car keys or the newspaper; she steered clear of him in tight spaces. At certain junctures, Reed wondered how long she was planning on keeping up the embargo. Of the two of them, Sadie had been the more physical—the first to initiate sex, the first to offer a back rub when Reed had had a bad day at work, the one who insisted on holding hands at the movies. One night Reed said, “You can’t get pregnant with your IUD in, you know, Sadie. No matter what I may or may not want.”

“I know,” Sadie had said. Her resistance to him seemed to have nothing to do with any actual fear of getting pregnant. Rather it was an act of hostility, of power, of torture.

Reed relieved his urges in the shower. He went for long bike rides. He stayed overnight at the hospital; the nurses commented on his devotion to the patients.

It was back in October, after nearly ten months of living without touch, kiss, or caress, when Reed bumped into Harper Frost at Morning Glory Farm. He had noticed the woman standing in line in front of him because of the pleasing way her ass filled out her jeans. When she turned around and he saw it was Harper Frost, the daughter of his patient Billy Frost, he was pleasantly surprised. Reed liked Harper for a couple of reasons. She was down-to-earth; she was concerned about Billy’s treatment but not uptight. She and Billy had a charming, irreverent repartee; Reed enjoyed listening to the two of them parry. Harper teased her father about his smoking, his drinking, and his legion of female admirers, and Billy teased Harper right back about her nagging him as though she were his wife or mother. He called her “my old lady.” The two of them seemed very close—they talked about scalloping, fishing, Dustin Pedroia and the future of the Red Sox, Billy’s handicap at Farm Neck (Billy claimed it was a three, but Harper said it was a hundred and eleven), and a restaurant in the North End that made a crab-and-artichoke ravioli they loved. Listening to them, Reed once again felt a pang for a child of his own. Who, he wondered, would take care of him in his old age?