“I have an idea for an experiment I’d like to run by those science people,” she said as she twirled a pipe cleaner.

“How much stress can people take before their heads actually explode?”

IT WAS 2:20 in the morning when Dan Hastings exited Butler, Columbia University ’s main library. Instead of heading toward the handicap ramp, the handsome blond freshman economics major smiled mischievously, zipped his iBOT wheelchair into stair mode, and rode the sucker all the way down the massive building’s Greek temple stairs.

You’d think I’d have learned my lesson, he thought as the expensive computer-balanced wheelchair bounced hard off the last step. His legs had become paralyzed in a mountain-biking accident.

He’d been on an extreme adventure trip to the Orkhon Valley in Central Mongolia with his dad. One second he was flying down a jeep track like the reincarnated Genghis Khan, and the next, his front tire got jacked between a couple of boulders.

His landing at the bottom of the ravine had pulverized his ninth, tenth, and eleventh thoracic vertebrae, but he wasn’t complaining. He still had his brain and his heart and, as a Mongolian parting bonus, the full use of his penis. With his iBOT, the so-called Ferrari of wheelchairs, he was putting the whole thing where it belonged. Behind him. He could and would continue to go anywhere he wanted.

Tonight’s late studying marathon was due to a mother of a stats test he had the next day. That, and the fact that his roomie was hosting a party for his Peace Studies group. He’d rather sleep in the stacks than hang with those tree huggers.

If truth be known, he was the biggest conservative he’d ever met. At liberal Columbia, that made him a spy, embedded deep in enemy territory.

His chair’s motor hummed as he opened it up across College Walk into Low Plaza. Usually, the area was filled with sunbathers and Hacky Sackers, but it was completely deserted now, the lit-up majestic dome of Low Library looking strangely ominous against the dark night sky.

Hadn’t the antiwar hippies taken over that beautiful building during the sixties? What a disgrace. What was even worse was that a lot of his fellow students still believed in that garbage.

Not him. He was an economics major. His original plan was to work his ass off, graduate summa, and get his ticket punched as an intern for one of the major Wall Street investment banks. But ever since Bear Stearns, Goldman, and Merrill had blown themselves up, he’d been thinking about trying to get on with a private-equity firm. He didn’t care which, just so long as it was big.

Go big or go home in a Med-Lift chopper was pretty much the Dan Hastings credo.

He popped in his iPod earbuds and scrolled himself up a little Fall Out Boy. That and My Chemical Romance were the greatest in wheelchair-cruising tunes.

He was passing Lewisohn Hall when he saw the light. A strange blue strobing coming from a doorway on its south side. Was it a cell phone? He slowed the chair and tugged out his earbuds.

“Hey, Dan. C’mere,” called a voice in a loud whisper.

What was up? Dan thought, zooming over. Was it somebody from one of his classes? College high jinks? Maybe it was a pantie raid. He was down with that. What was a pantie raid, anyway?

When he was about five feet away, Dan almost jerked out of his chair as he braked to a dead stop. A guy in a black pea coat and a ski mask stepped out of the doorway, holding a pistol.

What the fuck was this? And where the hell was Security?

He’d heard that Morningside Heights, the neighborhood around the Ivy League school, was notoriously dangerous, but he’d never heard of someone actually being mugged on campus.

“Take it,” Dan said, offering him the iPod. “There’s a hundred and fifty dollars and an American Express card in the wallet in my bag. You can have that, too, buddy.”

“Gee, aren’t you nice?” the man wearing the ski mask said as he grabbed Dan by his jacket and ripped him full out of the chair. The service door beside the man boomed as he kicked it open.

“What the fuck are you doing?” Dan cried as he was carried into the dark building.

The man hoisted him over his knee and violently wrapped his arms, legs, and mouth with masking tape.

“Shhh,” the man said, slinging him over his shoulder. “Quiet down now. No talking in class.”

“DAD, DON’T TRIP, and whatever you do, please don’t drop it!” Jane called after me as I zombie-shuffled over the curb toward Holy Name’s auditorium, bearing the awkward display boards.

Though the science projects were officially completed, this next stage was like on the Food Network show where the contestants have to move their cakes to the judging table.

Only I had to do it six times, and there would be no chance for a $10,000 check.

Once everything had been safely transported, I started to relax, though when I passed a blood pressure cuff on one of the gymnasium’s many displays, I was tempted to test mine.

I walked Chrissy to her kindergarten class’s door. She pulled away from me as I went to give her a hug.

“Not here, Daddy. They’ll say I’m a baby,” she told me.

But you are a baby, I thought.

“Can’t we at least shake hands, Miss Bennett?” I said. She gave me a quick, businesslike pump and bolted off without looking back. I smiled from the door as she linked arms and began whispering in earnest with one of her classmates. The kids were all growing up so quickly.

Thank God I, miraculously, wasn’t aging with them.

I was coming down the school’s front steps when I noticed that I hadn’t turned on my phone after charging it. No wonder my morning had been filled with peace and quiet.

Uh-oh, I thought. In the past twenty minutes, there had been two messages from my boss and four from Emily Parker. I called Emily back first. She was cuter.

“What now?” I said.

“The Fox Channel. Turn it on.”

I ducked into Holy Name’s rectory, adjoining the school. Mrs. Maynard, the parish secretary, looked up from stuffing envelopes at her desk.

“Father Bennett is still saying the eight o’clock, Mike,” she said to me.

“Is he? Could I borrow your TV?” I said, going into the lounge beside her without waiting for an answer.

“Live Breaking News,” said the text in the corner of the local Fox Channel’s screen. Across the bottom I read, MEDIA BARON’S SON MISSING. There was a shaky aerial shot of a college campus, probably taken from a helicopter. I recognized the granite dome of Columbia ’s Low Memorial Library. Police were laying tape by another campus building while a growing crowd watched.

“No,” I said into my phone as I finally made out what the police were cordoning off. The camera had zoomed in on an empty wheelchair.

I felt like borrowing the rosary beads around the crucifix on the wall beside the TV. He’d taken another kid? This horror was nonstop. Was that the point? Damn it, this was all we needed!

“Where are you now, Emily?” I said as I hit the street.

“Running to the subway. Columbia ’s uptown, right?” she said. “Don’t bother picking me up. I’ll meet you there.”