The story has all the stuff of a steamy summer novel. A large British defense contractor pays millions to a Saudi prince, and now Washington regulators are trying to figure out if U.S. banks played a role. A BBC investigative report reveals that a Saudi prince who worked out an $80 billion arms arrangement between Britain and Saudi Arabia took secret payments for at least a decade. According to the probe, BAE Systems ADR (OTC: BAESY), one of Europe's largest arms dealers, distributed hundreds of millions of dollars to the ex-Saudi ambassador to the U.S., Prince Bandar bin Sultan. Evidently, money changed hands with the full knowledge of the U.K.'s Ministry of Defence. Neither the Prince, nor the Defense Ministry would comment on the arrangement.

Former BAE chief executive Sir Raymond Lygo told the BBC there was "nothing untoward" about the arms deal, but he had nothing to say about the payments to the Prince. Britain's Serious Fraud Office first revealed the payments. It was trying to figure out whether or not they were illegal under British law when the office's investigations were halted out of fear of angering Saudi authorities, according the the BBC. They stopped in 2006. Prince Bandar is well connected. His father is the Saudi defense minister. The Prince now runs the Saudi national security council. He served as U.S. ambassador for two decades and the payments allegedly were funneled through Washington bank accounts.

The American connection: Marketplace reports that there are two key U.S. links to this story. The U.S. Department of Justice is taking an interest in the imbroglio because if it's true that money went through American banks, the case would fall under scrutiny of U.S. authorities. What's more, there's a political connection. The Pentagon is a huge customer of BAE. If anyone can think of a better plot line than the one threading this story, send us your ideas.