After his latest invention fails, Dex is welcomed back by Ed to his old job at Good Burger, which is once again put in jeopardy when Dex devises a plan to get back on his feet.

Big Nick is back on the hunt in Europe and closing in on Donnie, who is embroiled in the treacherous world of diamond thieves and the infamous Panther mafia, as they plot a massive heist of the world's largest diamond exchange.