In his freshman and sophomore years, Henry Lu spent the Thanksgiving weekend on campus at MIT . The break was too short to make the six hour flight home to San Francisco worthwhile, and anyway his family didn’t really celebrate Thanksgiving, calling it a “European holiday.”

Henry used the time to work out linear algebraic equations, with football on the TV behind him, and traffic from Massachusetts Avenue beyond that.

Junior year, however, Henry’s roommate Aaron Mullins invited him to spend the holiday with his family.

“It’s not healthy to be by yourself,” he said. “You’ll turn into a Scrooge.”

“Will I have to milk a cow?” Aaron lived out in the Berkshires.

“If you want.”

So Henry agreed to go. It was a splendid Thanksgiving; Football in the yard by day, turkey by night. Henry couldn’t recall ever feeling so refreshed.

But Henry was from the city. He was unaccustomed to the actual quiet of the country. Henry lay in bed, unable to sleep.

And at 1:03 AM, Henry became aware of The Pulse.