When the lottery jackpot reaches $140 Million, Peter takes out a second mortgage on the house to purchase 200,000 lottery tickets in the hopes of winning. He first fools his family into spending 3 days going through them before revealing he'd had 400,000 additional fake lottery tickets printed up before revealing the real ones. Brian finds the winning ticket and they become millionaires.
Peter proceeds to buy time with his friends, coercing them into doing what he wants all the time. Lois begins to notice the change in the family's behavior due to their wealth, but her mind is quickly changed when Peter gives her a golfball-sized diamond ring. They squander all of their money and the remainder of it that's in a foreign bank account was ruined to the point that Peter didn't want it back. Now broke, the bank forecloses on their account, leaving them homeless. Peter buys another lottery ticket and they win again, but immediately end up right back on the street when they again waste the money, much to Carter Pewterschmidt's glee who knew they'd waste the money.
Broken and humbled, Peter asks Joe and Quagmire for help. Quagmire, who had gone into a bit of a business for himself writes Peter a check to get them their home back. In the end, the Griffins are back where they started, no richer or poorer than before, and they are all content with that.