I was too vague.  Or too specific.  I can't tell.
Anyway, what I was wondering was what do you do with those 2 hours of the session that remain, assuming that getting back into the game with a PC of any sort -- see my OP -- is out of the question.  Go home?  handg out and watch?  Read?
If you are the DM, what do you do when you've got a player who is out of the action for what looks to be the rest of the session?  let him sit there like a lump?  Engage him somehow? 
Or if you are another player, who still has a live, active PC to worry about, but your friend Bob is stuck twiddling his thumbs?