"It's not bad in here," Jack replied, by which he meant that he would promptly turn the controls down so the ambient temperature was below zero, but that could wait until Bruce didn't have to stand around in it.

He wants to touch everything and so he does, hands running over walls and furniture and fabrics as though memorizing them. His tactile exploration leaves tiny little bursts of hoarfrost and he's utterly delighted that it doesn't melt off right away.

"How did you two do all this? Was it really easy for you 'cause you're so smart? You're sure it won't hurt the tree? Is this the weirdest thing you've ever built?"