I think Des goes back after a bump on the head like that. He was aware of the fact he wasn't supposed to be there when he woke up covered in paint, and his friend and him were talking about time travel.

__________________
" I push this button every 108 minutes, I don't get out much."

"Theres a time for living low down, theres a time for getting high. A time for peace, a time for fire. A time to live, a time to die."

The real art of conversation is not only to say the right thing at the right time, but also to leave unsaid the wrong thing at the tempting moment.