The "jump the shark" reference comes from the old show, Happy Days. For a long time, it was clear the writers were out of ideas, so they had "Fonzie," complete with leather jacket, do a water-skiing episode where he jumps over a shark. It's a classic meme for having gone so far as to be ridiculous.

Personally, I think the original concept had a more interesting premise, what with the webs and all. Throw in some echos and spiders (not the Starship Troopers stuff), and what-not, and caves, and it could have been very interesting. I had been looking forward to it.