Then one night I happened into American Seasons for a celebratory drink. I had just sold my first house, a fixer-upper on Pilgrim Road, listed at $1.2 million. The listing broker had to get home to his family, but my boys were at football practice until seven, so I had a couple of free hours. I didn’t think anyone would be at the bar at American Seasons at five o’clock-but I was wrong. When I walked in, Flynn Sheehan was sitting there alone, with a tall beer in front of him.

I said, “Flynn, hi! Tammy Block, I’m the one who rents the…”

“Reilly house,” he said. He gave me a sort of half smile, and I thought my heart would stop. “Like I could ever forget you.”

I have gone on long enough, and the story from here takes a bad turn. Some people had neat and orderly lives, and some people’s lives were messy and morally ambiguous. I have lived the latter. Did Flynn and I have an affair? Yes. It pains and embarrasses me to confess that. Did Amy Sheehan-who was, in anyone’s objective opinion, a miserable woman-discover the affair by looking at Flynn’s cell phone records and spread the news of my slutty debauchery all over the island? Yes. Was I ready to pack up my belongings, uproot the kids, and move off the island? Yes.

There were only two reasons I didn’t do this. One was: I loved Flynn Sheehan with every fiber of my being. After Amy smeared our names like blood all over every street in town, he had a difficult choice to make. He could try to repair his marriage and salvage his family, or he could leave. He called me up at eleven o’clock on the night the news broke and said, “I left her, Tammy. I love you.”

The other reason I didn’t leave Nantucket was because of Dabney Kimball Beech. As soon as she heard the news, she knocked on my front door. I ignored her. I didn’t want to hear her lecture. Surely anyone with a life as perfect as Dabney’s would never understand adultery-even though, technically, she was the one who had set me up with Flynn.

When I didn’t answer the front door, she knocked on the back door. When I didn’t answer the back door, she started tapping on my windows. I had to hide in my powder room, where she couldn’t see me. But she was relentless, and finally I gave up. I let her in the back door and waited for the beatings to begin.

She hugged me. Then she sat down at my kitchen table. She said, “I am going to hold your hand until you stop crying.”

I cried for quite a while. I cried and cried. When I finally stopped to blow my nose, I said, “Why did you send him to me when you knew he was married?”

“Because,” Dabney said, “you two are a perfect match. You’re meant to be together.”

Dabney was right. Flynn divorced Amy and married me on the beach in Madaket with only our children and Dabney and John Boxmiller Beech in attendance. There are still people on this island who won’t speak to me, who won’t meet my eye in the supermarket, who wouldn’t give me a referral for a sale if I were the last Realtor left on Nantucket. But I have Dabney-and she is not the person she appears to be.

She is so much more.

Dabney

She was beside herself with excitement. Agnes’s Prius was due to arrive on the five o’clock ferry. It wasn’t just a weekend visit; it wasn’t a few days at Christmas. She was really staying the entire summer!

Unfortunately, Box was going to miss Agnes by a matter of hours. He had come to Nantucket for the weekend, but that morning Dabney had delivered him to the airport. He would go back to Boston tonight, and fly to London in the morning. He would be gone two weeks.

“I feel like we never see each other anymore,” Dabney said.

“The lives we lead,” Box said.

Dabney clung to Box tightly, which he seemed to resist, and when she raised her face, he kissed the tip of her nose like she was a child.

“Please, no more histrionics,” he said. “It doesn’t become you.”

“Histrionics,” Dabney said. “That sounds like a newfangled major at Harvard.”

“I was referring to the middle-of-the-night phone call last week,” he said.

“I know what you were referring to,” she said. “I was trying to amuse you.”

“Waking me up in the middle of the night to ask me questions you already know the answer to isn’t amusing.”

“I’m sorry,” Dabney said, although she had already apologized three separate times over the weekend.

He patted her shoulder. “I’m off,” he said.

He grabbed the handle of his carry-on and strode toward his gate.

“I love you, darling!” she called out after him, but this must have qualified as histrionics because he didn’t respond. He didn’t even turn around.

Dabney planned to leave the office at four thirty so she could get home before Agnes arrived, but just as she was packing up, her computer chirped. She checked the screen. E-mail from Clendenin Hughes. Subject line: Fried rice.

Delete it, she thought. Agnes was on her way. Delete it!

The lives we lead. She opened the e-mail. It said: Come to my cottage for dinner tonight. A crate arrived today with my wok in it. Please? 8:00.

She was tempted to respond: I can’t. I’m having dinner with Agnes.

His daughter.

She was tempted to respond: No. No way. But she feared that any response, even a negative one, would only encourage him.

She deleted the e-mail, then deleted it from her deleted file.

Dabney was standing in the driveway when the Prius pulled in. She was aghast to see CJ behind the wheel.

Agnes climbed out of the passenger side and ran to hug her mother. “I’m here!” she said. “I can’t believe all of my stuff fit in that tiny car!”

CJ greeted Dabney with his usual enthusiasm, like she was the only person in the world he wanted to see. He smelled wonderful. He said, “I didn’t want your daughter to have to do the drive alone.”

“Of course not,” Dabney said. She swallowed. “How long can you stay?”

“I’m flying back at nine o’clock tonight with my client, whisper whisper.” CJ winked at Dabney. “Private plane.”

Dabney hadn’t heard the client’s name-either she was losing her hearing on top of all her other maladies, or CJ hadn’t meant for Dabney to hear. She didn’t care; she was relieved that CJ wasn’t staying over.

“I have chicken marinating,” Dabney said.

“I took the liberty of making dinner reservations at Cru,” CJ said. “You’ll join us, I hope?”

Dabney faltered. Were they really hoping she would join them, or did they want to be alone? She felt a wave of exhaustion and weakness; the pain in her abdomen had returned with a vengeance. The antibiotics had done absolutely no good. She supposed her next step was to stop eating wheat. Goodbye to her morning cereal. Goodbye to her beloved BLTs. She might as well stop breathing.

“Please come, Mommy!” Agnes said. “You love oysters!”

Dabney adored Cru-it was chic, polished, and fun. That evening, the restaurant was offering nine kinds of oysters, and Dabney decided to order three of each.

“Great idea,” CJ said. “I’ll do that, too.”

Dabney and CJ’s oysters were presented on an iced platter roughly the circumference of a Goodyear tire. Dabney doctored her oysters the way she liked them-fresh lemon first, then horseradish, then half with a dab of cocktail and half with mignonette.

“Ah, now see,” CJ said. “I’m a purist. I eat them naked.”

The server had brought them a list of the oysters, which ran clockwise around her platter so that they could identify each one.

Dabney beamed. “It’s like a party game!”

CJ had ordered a drink called a Dirty Goose, which came in a martini glass, and he threw it back in one gulp, then spun his finger at the waiter, indicating he wanted another. There were hot rolls on the table. Dabney’s first challenge in not eating any wheat was to skip the rolls. She nudged the basket toward Agnes.

“Have a roll, darling. You’re far too thin.”

“I’m fine, Mom, thanks,” Agnes said.

“CJ, would you like a roll?” Dabney asked.

“No, thank you,” CJ said. “Agnes and I don’t eat carbs.”

“You don’t?” Dabney said. This was news to her. Agnes looked like she could use a big plate of fettuccine Alfredo every day for the next month, but she knew not to press the matter.

Dabney ate the Belon from Maine, then the Hama Hama from Washington State, then the Kumomoto from British Columbia, which was an all-time favorite of hers.

“Would you like one, Agnes?” she asked.

Agnes studied the platter. Of course she wanted one! Dabney and Box were oyster connoisseurs; it was one of their few extravagances. Box ordered twelve dozen Blue Points and twelve dozen Kumomotos for their annual Christmas party. Dabney made a homemade mignonette with crushed fresh raspberries. Agnes had grown up with oysters the way other children had grown up with Pepperidge Farm Goldfish.

“No, thank you,” Agnes said.

“Please, honey, help yourself. We can always order more. How about the Island Creek?”

CJ polished off his Dirty Goose and set the empty glass down so hard on the table that Dabney was surprised it didn’t break.

“No, thanks, Mom,” Agnes said.

“If Agnes wants an oyster,” CJ said, “she can have one of mine.” He lifted one dripping out of its shell and fed it to Agnes like she was a baby bird.

Dabney felt a combination of helplessness and anger rise in her throat. She ate a Wellfleet.

CJ said, “So, Dabney, you’ve succeeded in stealing my fiancée away from me this summer.”

French Kiss from Nova Scotia. Dabney accidentally took a hit of horseradish up her nose, and she reached for her water. “Pardon me?”

“I hope you’re happy.”

“I…?” Dabney looked to Agnes for help. Agnes’s eyes were wide and imploring. Dabney realized that she had been set up as some kind of fall guy. “Well, really, I…when Agnes told me about the funding issue at the club…”

“Agnes doesn’t have to work again, ever,” CJ said. “At the club, or anywhere else. I’m more than able to take care of her in the manner to which she’s been accustomed, and then some.”

“Right,” Dabney said. “I realize this…”

“But you wanted her here at home. I get it, your only daughter back in her childhood bedroom for the summer. Before she gets married and leaves you forever.”

“It’s not like that,” Dabney said. Agnes had now bowed her head; her chin was tucked to her chest. She wasn’t going to say a word in her own defense, or Dabney’s. She was afraid of CJ. Agnes, who had been sailing and water-skiing since she was five, who had flown to Europe by herself at the age of fifteen, and who routinely took the subway home from 125th Street at night in the dark, was afraid of CJ Pippin. She clearly hadn’t told him that it had been her idea to come home to Nantucket. It was she who wanted the beach and the familiar house and the comforting presence of her parents and a chance to work one last summer at her old job as an adventure counselor.

Suddenly their table was engulfed in a ghost-green miasma that was only too familiar to Dabney.

A third drink arrived for CJ, another Dirty Goose. He said, “I’m not going to tell Agnes she can’t go. But I’d really like her to come back to New York every weekend. And if not every weekend, then every other weekend.”

Dabney felt for a second like she and CJ were divorcing and discussing a custody arrangement.

“You can come here anytime,” Dabney said. “We have plenty of room.”

CJ snorted and took a healthy pull off his drink.

“I’m forty-four years old,” he said. He glanced at Agnes, who now had her hands clasped at her chest like a praying mantis. “I’m past the point where I want to stay in someone’s guest room. If I come back this summer, I’m going to want my own place with Agnes, so we have the necessary privacy. But it’s a little late to start looking, and I’m unsure of which weekends I would even be free enough to travel. My clients, Dabney, are really just kids-some of them only nineteen and twenty years old. I need to be available for them twenty-four/seven. Summer is a busy time, especially for my NFL players. I assume you’ve heard of Bantam Killjoy?”

Dabney had not heard of Bantam Killjoy. Was he talking about a person? Or a new video game?

Dabney shook her head.

“He was the number-one draft pick, wide receiver out of Oklahoma, nominated for the Heisman. Big media favorite because both his parents were killed in the Oklahoma City bombings when he was a baby.”

“It’s a really sad story,” Agnes said. “With a happy ending. But Bantam needs CJ’s guidance, almost like an older brother, or an uncle.”

“Yes, I’d imagine so,” Dabney said. “I’m sorry. I don’t follow college football except for the Harvard-Yale game.”