Something took over Jack. Some creature got inside his best friend's head and drove him out of his mind and caused him to kidnap (and god knows what else) someone. Something evil and dark possessed his brother.

Inwardly, Carl is seething.

Outwardly, he's watching Jack closely, and notices the white-knuckle grip he has on the chair.

"Jack," he says softly. "Why don't we sit, huh? S'been a long couple of days."