Radley, his first post-Lauren friend, was a relief by comparison. He was often free, leading Josh to believe that either Radley didn’t have many friends either, or he was using Josh as a guinea pig for therapist training. Either way, he was grateful, because there were days when it felt like he didn’t really exist. That, were it not for a text from Jen here and an invitation from Radley there, Josh felt like he might not be . . . real, somehow. He talked out loud from time to time just to make sure he still had a voice. Pebbles would lift her head and wag, or come over and sit close to him, pressing herself against his legs.

He was so glad he had a dog.

The forum said everything was normal. Others understood and commiserated. It didn’t make the problems go away.

One day, Josh was contacted by Chiron Medical Enterprises, a company based in Singapore who’d bought one of his designs. They wanted a device that would help spinal surgeons detect different tissue types in the back to alleviate human error when inserting hardware, limiting damage to soft tissues and especially the spinal cord. It was a good project, complicated but with far-reaching benefits, right up his alley.

The more he sat at the computer, the easier it became to think about the job. His tunnel vision returned, the thought process that had allowed him to succeed so early in life.

He and Lauren had once watched a movie or TV show that depicted some young genius—Sherlock Holmes, maybe, or Alan Turing. The character saw various elements floating in patterns and connections that lit up, invisible to everyone else. Lauren had paused the movie and asked, “Is that what it’s like for you?”

“No,” he’d said slowly. “It’s the opposite. It’s literally tunnel vision. I see the problem, and the next sixteen steps, with the complications sitting on the road ahead, like hurdles I have to jump to keep going. Everything else is blocked out—what time of day it is, if I’m hungry, if it’s night or day or raining or sunny. There’s just the path to the solution. I think . . . well, I think I’m different because I can shut everything else out and see to the end of the tunnel.”

She’d looked at him a long time. “You’re remarkable, you know,” she said, running her fingertips up his cheek, touching his earlobe. “Utterly remarkable.”

He’d been unable to invent anything to help her, though.

Move along, loser, he could hear her say.

Finally, the morning came when Sarah dropped off the fifth letter. It had seemed like an eternity since the last one.

“Want some coffee?” he asked. It was a test for himself to see if he could wait, and also to try to be a good friend to Sarah, who missed Lauren, too, of course.