It is a lot of fun I did it for the first time this yr about halfway through, they present a story chapter each week that you read.
Then you go down to the bottom of the page and you need to visit all of the stores to find clues (some are really well hidden). When you finish that they give you a detective whether it's answering clues, doing word scrambles of various people/places, you email them the answers and your name gets added for the weekly draw for various prices.
It's totally random it doesn't go by who answers first. You get where your checking your email each week to find if the next chapter is ready.