In nearly every romance ever portrayed on paper or screen, there is always something that threatens to separate the happy couple—another person, a war, an illness, an iceberg. But in Jonathan Lethem’s “As She Climbed Across the Table,” never before has the threat been so real ... and yet so nonexistent.

Sociologist Philip Engstand is madly in love with his girlfriend, Alice Coombs, a particle physicist. The book, narrated by Philip, opens with the unveiling of an experiment Alice and her coworkers at (fictional) Beauchamp University in California have been working on. They have created a void in the universe, an actual little black hole right in their lab, hovering over a table. Immediately, Alice is drawn to the space, which the scientists have taken to calling Lack. She starts spending late evenings at the lab with Lack, which worries Philip. What he thought was an extreme interest in her work turns into a rift in their relationship. Alice cancels all the classes she teaches and starts spending all her time in the lab. Lack has started showing hints of a personality, exhibiting an ability to make choices, and Alice spends her days testing Lack’s choice in items. She pushes things across the table, into Lack. Some pass right through to the other end, but occasionally, something disappears inside.

“She fished in her pocket, brought out a dime. The dime slid through and fell. So did a penny, and so did a ballpoint pen. Alice emptied her pockets into a pile on the other side of the table, and each item clattered to the lab floor, refused.
Alice went and gathered her belongings. One was missing. She searched the floor, frisked herself, reloaded her pockets, conducted an inventory. It was nowhere.
Lack had gobbled the key to our apartment.”

Shortly thereafter, Alice stops coming home and begins sleeping on a cot in the lab beside Lack. Philip is hurt and confused. He hadn’t really thought about the fact that he could lose her to another man, so losing her to a void is almost unimaginable. He starts pestering her at work, following her around in secret and trying to sabotaging her press conference about Lack, all to no avail. Alice is in love.

“You love Lack. The way you used to love me, but don’t anymore.”
She sighed. “You keep repeating it, Philip.”
“Then it’s true.”
“Yes, I love Lack.” She didn’t flinch or falter. She was comfortable saying it now.
“I was too real for you. You wanted to meet someone imaginary.”
“Lack is real, Philip. He’s a visitor. An alien.”
“Lack’s an idea, Alice. He’s your projection.”
She stared at me defiantly. “Well, he’s a much better idea than a lot of others I can think of. He’s the idea of perfection, the idea of love, of perfect love.”

Lethem’s book is incredibly smart and sexy, and his ideas are refreshingly original. (His award-winning follow-up, “Motherless Brooklyn,” is about a detective with Tourette’s syndrome.) As sad as the idea is of Philip losing the woman he loves, the story is clever and funny, and the dialog snaps. Perhaps the best scenes are with Evan and Garth, two blind men who want to talk to Alice about an experiment and end up visiting Philip at his place after Alice moves out. They’re like the blind Greek chorus of the book, offering up wisdom and advice, though still occasionally getting a few details wrong.

“This chicken is very good,” said Evan.
“We rarely have chicken,” said Garth.
We were eating fish. I said nothing.

Easily the best boy-meets-girl, boy-wins-girl, boy-loses-girl-to-a-black-hole (of her own accord) story out there. And science-fictiony in a way that only Vonnegut or Atwood usually are. Let this book be a lesson to anyone who doesn’t realize all the things they have to be afraid of when it comes to romance, and a delightful treat for those who worry that much already.