Henry Smith's brother, Franklin, has been knocked down by a car and seriously injured while out jogging. In fact, his injuries are so serious that they've put him into a coma. It's touch and go whether Franklin will survive. Henry and his parents make their way to the hospital, where they spend as much time as possible next to the stricken Franklin's bedside.

On that first terrible night after the accident, Henry spends all night in a vinyl chair by Franklin's bedside, where one of the nurses puts a striped blanket over him. This will be one of many such nights that Henry will spend by the side of his seriously injured brother. Before long, Henry will practically become part of the furniture at the hospital.

It's while he's keeping vigil over his brother that Henry has a truly remarkable experience. Franklin briefly wakes from his coma and utters the word “Katahdin,” which is the name of a mountain peak in Maine that he was planning on climbing prior to his tragic accident.

When Franklin eventually passes away, Henry resolves to climb Katahdin himself in his late brother's memory. But as subsequent events will show, this turns out to be a much more complicated endeavor than he'd originally imagined.