It's a Ponzi scheme! They're promising you a 20% return as long as there are greater fools around that are willing to bet they're not the greatest fools. I love it.
The gamble is that you will not be the last idiot to invest (the last person/group is the loser). Basically the first people give their money to 1 address. The group that follows pays the first their 20% return (+ the operator's 5% fee it looks like).
Where in a regular (regulated) scenario, your investment would be paid back by the company's sales, profits, liquidity, assets, ect. The people who participate in this gamble that they are not the last to invest (and that the operator pays out), because the "return," is dependent on the next following "investor."