It's hard to watch a pro sporting event on TV without seeing an ad for FanDuel or DraftKings, the two largest daily fantasy sports (DFS) sites. The industry came out of nowhere in the past six years and now serves millions of sports fans nationwide. Both companies have major, deep-pocketed backers and sport billion-dollar valuations.

But the very foundation of the game could be crumbling.

First came the allegations of insider trading, followed by a more fundamental threat: In the past several weeks, states including Nevada and New York have outlawed DFS, declaring it gambling as opposed to a game of skill. Both sites remain closed for business in the state of New York, but the outcome of an emergency hearing could further crystallize the fate of this industry.

For players, meanwhile, this is perhaps the most explosive revelation of all: A recent report indicated that about 1% of the players take around 90% of the profits.

With all this hanging in the balance, we dove into the deep end to meet the sharks (big winnings), the big fish (major losses), and the minnows of the DFS ecosystem. We wanted to examine the core question of whether DFS is a game of skill or whether it's gambling. And most of all we wanted to know: Can it actually pay to be a fan?

Executive Producer: Diane Galligan

Producer: Andrew Stern

Cinematography: Sam Rega