During the break for lunch, I find Ivan lounging by the pool. He looks relaxed and tan, splayed out with a Business Week by his side. He has lots of hair on his chest -- the emblem of the alpha male. Though quite a few people are using the pool, all the nearby chaises are empty. I attribute this to Ivan's formidable air; he carries it with him like a force field. But there are moments when it evaporates. Like when he plays the piano.

"Where's Jason?" he says.

"I have no idea."

"I thought you took him shopping."

"I didn't take him shopping. Why do you think I took Jason shopping?"

"Because you said so," Ivan replies.

"When?"

"A little while ago."

"I didn't say that."

"Yes you did."

Oh no. I think I see what is going on here. But Ivan would never fall for it. Besides, Samantha hasn't tried this for a long time, not since my high school boyfriend, Brian, the football player, bought himself a baby blue convertible.

"That wasn't me. That was my sister."

"Oh," Ivan says mildly, as though I'd just pointed out an interesting item floating in the pool.

"Don't you know me?"

"Of course I know you."

I feel so angry -- I don't think I've ever been so angry at Ivan. "She doesn't even look like me. Her hair is streaked, she smokes, she's thinner, she acts all ... whacked out. Ivan! Look at me."

He looks at me, calm and patient, the man I married. Solid. The man who flies off the handle at everyone except me.

"This is me. I'm not her. Look at me. My breasts are bigger."

"Your breasts?"

"Ask Jason. He knows."

"Amanda, what do you expect? If you girls are up to tricks like that -- identical twins," he squints at me through the sun. "Any jury would find me innocent."

"I'm not up to anything."

"You said you'd take him shopping." He closes his eyes and settles his bald, bronzing head on a rolled-up towel. "Somebody took him away, thank God."

"It wasn't me."

"I know."

"She's not me."

"Of course she's not."

Of course. Everyone thinks we're the same. Why should I expect Ivan to be any different? We even think we're the same. That's why we can only stand to see each other once every four years. Who wants to watch her identity be swallowed by her genetic double? I certainly feel the poorer for it. The only people who seem to profit are the researchers. They get to learn whether we both stutter or get cancer of the pancreas; they get to learn whether we both marry swarthy plumbers or enjoy table tennis. They seem so sure that twins hold clues to the mystery of identity: what depends upon threads of DNA winding and unwinding in our cells, and what do we glean from the world? Kevin and his friends are trying to study what makes each of us us -- but not us per se, not the twins. We're the freaks. They want to know what we mean for normal people. Why do normals divorce, sicken, hate licorice, refuse to perform certain sexual acts? Is it genetics or environment? As if the data could ever tell us why we feel the way we feel.

I order a drink and settle into a chaise. After a while, Samantha shows up. She's riding Jason's skateboard, with the pug laboring at her side. Poor Diego. I don't know what she was bred for, but it wasn't running. Jason trots along behind them. Under his curtain of bangs, his face looks different.

"Check out my shirt!" He points at his chest where the words DESIGNATED DRIVER stretch across in big, iron-on letters. I grasp what it is about his face: he's smiling.

Samantha jumps off the skateboard and plops down beside me. "All these thrift stores around here are unbelievable. We found the greatest stuff." She reaches into a plastic bag and pulls out a green bowling shirt. On the back it says SEVENTH DAY ADVENTIST DENTISTS.

"That's really funny."

"Want it? It's one of a kind."

"Yes." I'm surprised by myself, because usually Samantha is the one who wears the thrift store shirts. But I can't pass this one up. "I hear you met my husband."

"Uh huh."

"He thought you were me."

"He did?" Samantha looks surprised.

"Did you tell him that?"

She looks like she's tasted something sour: this is our lying face. "I don't think so."

"It's a yes or no question."

Samantha is leaning back next to me on the chaise, curling and uncurling Diego's tail. Jason has pulled up a chair beside her. He gazes at her with adoration. He says: "Hey Dad!"

Ivan, sunbathing and half-asleep, grunts.

"Samantha took me to this restaurant where we ate balls of raw meat!"

"It's Armenian," she explains.

"We fed some to Diego."

"She liked it." Samantha is wearing a bikini top and jeans. She's as brown as maple syrup and has muscles all up and down her arms and shoulders. I guess she's been going to the gym.

"You shouldn't eat raw meat." Ivan's eyes are still closed. "You'll get cholera."

"Samantha did it."

He looks up. "That's bright. If she jumped off a cliff, would you follow?"

Jason cocks his head. "Maybe."

"Beautiful. I'm going in the water." Ivan ambles off and wades into the pool, holding his magazine above his waist.

As soon as he's gone Samantha turns to me, her hands folded in her lap. "Your husband is intimidating. His aftershave smells like money."

"That's because it's expensive," I snap. Diego is leaning against my leg. I bend down to pet her. Something is bothering me. Something is bothering me a lot.

"Samantha, why can't you be my stepmom?" Jason says, right on cue.

"She's your stepaunt," I tell him. "You can call her Auntie Sam."

"Don't call me Sam," she says. "She's saying that because I hate it."

"You should wear sunscreen," I tell Samantha, "you're too tan." I can feel us falling into something; our rhythm -- it's like loneliness and the antithesis of loneliness at once. And it really is like falling, exciting or terrifying, depending on what's below. I don't think there's any stopping it. I say: "Kevin has a hate-crush on me."

"Who's Kevin?"

"The one with the little Lenin beard." I pick up Diego and put her in my lap. She starts licking my hand.

"Right, with the funny eyebrows. Did you engender the hate, or is it women in general?"

"What's a hate-crush?" Jason asks.

I ignore him. "I think his wife engendered the hate. But now it's directed at women in general."

"What are you guys talking about?" Jason looks at us sideways. "Is this your secret twin language?"

"No!" we both say, in unison.

Samantha turns to Jason. "A hate-crush is when a man likes a woman a lot, so he's mean to her."

For some reason, this makes Jason blush. "I thought that was over in third grade."

"No," Samantha says. "Sadly, no. Promise me you won't do it. It's extremely uncool."

"Okay," Jason says.

"Be nice to the girls you like. Even if it's a little scary."

He's nodding, really soaking it in. It occurs to me that Samantha may be changing the course of his entire life.

She holds up the nametag that says MZ SAMANTHA 173 and tries to pin it to her bikini strap. "I don't have anywhere to put this."

"That's what you get for not wearing a shirt."

"Wait," Samantha smiles, "check this out." She takes the pin and pushes it through the tough skin of her outer elbow. She fastens the clasp. It stays there as she flexes her arm.

"Wow," says Jason.

"That's disgusting," I say.

"Come on," she tells Jason, putting on her sunglasses, "I have an appointment on the inside." They gather their things and go into the hotel. It takes me a while to realize she's left Diego with me. Samantha never has been very good at taking care of things.

- - - - - - - - - - - -

No one has asked for my opinion of the California Twin Study, but if anyone did I'd say they should stop doing all the things that make us feel like rats. The lines of colored tape in the hallways that usher us from room to room are especially inane, and after certain tests we are offered doughnuts -- why not lumps of cheese? Then there is the underlying philosophy to all this testing, that any information we may be given is too much information. So I go into a room, I lie on a padded table, and a woman in a white coat tapes ice-cold electrodes to my head. When I ask her what they're for, she says, "Taking measurements." When I ask what kind of measurements, she says, "Important." Then she leaves me in the half-darkened room, with instructions to relax. But I know what they're doing: measuring my brainwaves to see if they match Samantha's.

For a while I try to think my own, idiosyncratic thoughts; then that seems too Samantha-like, so I go for some dull, average thoughts; then I realize this is the same road I went down with the personality test. I don't have any of this figured out anyway. I don't know how much of me is a part of her no matter what. We grew up together. We're the same genetically. Maybe the desire to be singular is just another thing we share, and somewhere, in some other room, Samantha is lying with wires attached to her head trying to think thoughts that I wouldn't think. Finally, I give up trying to be original and fall asleep on the table. Almost immediately I begin to have the dream: The ocean swells, enormous waves sparkle in the sun and rise above the beach. Then, the entire shoreline is swallowed up -- houses, cars, cliffs, beach umbrellas -- they're all washed away, and all that's left is a great expanse of blue water: nothing. Everything.

After the session, I find Samantha sitting on the carpet in one of the long hallways, slumped over a line of yellow tape. She's crying.

I sigh. "What's wrong now?"

"You're married." She wipes the snot off her face. It's a nice face, somehow prettier on Samantha (I even got Kevin to admit this), more transparent and broad. It's a little icier on me, with a knot between the eyebrows.

"So what?"

"You're just ... normaller."

"You say that like it's a good thing."

"It is good. You're the good one, remember?"

I laugh. "Okay, let's get this out in the open once and for all. True or false: I have a tender spot on the top of my head."

"True!" Samantha touches her part. "Right here. It drives me crazy!"

I touch my own head and am surprised to find I have a tender spot there too. I try another. "True or false: I would certainly like to beat a crook at his own game."

"True! Wouldn't you?"

"Yes. Do you always answer them truthfully?"

"Of course." Samantha sniffs. "How about you?"

"I try to pick whatever one I think you wouldn't."

She laughs at this. "Then you must switch it."

"Yes." I feel dispirited. Of course Samantha knows all about me and my ways.

"You always did love to lie," she says.

"You left the dog with me."

"I did?"

"I'm not keeping it."

"I know."

I look at her, her face red from crying. I can't remember the last time I cried. Even Ivan, when we got married, became a little teary. But not me. I'm the stable one.

- - - - - - - - - - - -

At the end of the day, Kevin locates me and apologizes. His eyebrows are smoother and he looks embarrassed. Too much work, he explains, shoving his hands into his pockets. Way too much coffee. Then, as a peace offering, he tells me what it is he's learned about Samantha: she's pregnant. And, in the grand tradition of the California Twin Study, no one has mentioned this to her.

He doesn't know if she knows.

I think about this through dinner and afterward, in our rooms, where Jason refuses to settle down. Ivan tells him he can call for room service, he can order Nintendo with the remote, but he keeps jumping on his bed like a little boy while Ivan repeats "Jason" in a threatening tone.

"So what do you think about Samantha?" I lean up against the doorjamb between our rooms. "She's kind of a loose cannon, isn't she?" "

She's okay," Ivan says. "Jason!" Jason jumps higher. Hanks of greasy hair stream upward from his head. Ivan looks at his watch. "She's not as unpleasant as you described."

"I" -- Jason jumps once on each word -- "like, her, more, than" -- his face is turning red -- "either, of, you."

"For God's sake, stop that," Ivan says.

"You should have seen her before. She's reformed or something. She used to be even more, I don't know, disturbed. She took drugs."

"She didn't seem that disturbed to me," says Ivan.

Jason is now making a va sound with each jump, like a car that won't turn over.

"You can tell she's nothing like me, though, can't you?"

Ivan laughs. "Well, there are similarities."

"I can tell," Jason chants.

"Excuse me, I was asking your dad."

"Boy, can I."

"Okay Jason. I'm asking your dad."

"Jason, stop that right now," Ivan roars.

"He isn't going to stop."

"Jason!"

"He isn't going to stop until you quit telling him to."

"Jason! I said now!"

I go back to our room and turn on the TV. Finally, Ivan comes in, shuts the door to the adjoining room, and bolts it. I can hear the squeak squeak of Jason jumping on the bed for a while, even as Ivan eases me down on our own bed and starts pulling off my blouse. He lies beside me and unclasps my bra. Jason has quieted down, but then he starts knocking at the door. Lightly, at first, but then he's pounding and crying "Dad" in a scared voice. I guess thirteen isn't really that old. Two or three years ago, he would have been too young to leave without a babysitter. I guess I should feel sorry for him. But mostly I feel annoyed.

"Jesus," says Ivan. He excuses himself and slips into Jason's room. I brace myself for another round of screaming but don't hear anything for a long time. Then I hear Ivan's voice, very faintly, coming through the door. He's not yelling. He's singing.

- - - - - - - - - - - -

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