Okay... Everyone knows the morale "Don't judge a book by its cover' Its being so overdone in TV Shows. Aside from that, this episode also didn't deliver well. I thought it had few laughs and too much other things going on. I found the fat girl (sorry the name I forgot) wasn't really interesting or funny or much of anything I found her quite pale in characteristics and just plain awkward when she and Will were on screen.
IMO, not a must see episode