Ted Kaufman is something of a hero to people like me. He is the longtime Joe Biden aide appointed to fill Biden’s Senate seat in 2008, who used the opportunity to make Wall Street squirm. His signature proposal was the Brown-Kaufman amendment to the 2010 financial reform bill, which would have split each of the country’s three biggest banks roughly in half. The proposal died after a tough fight in the Senate, but it established Kaufman as one of the most serious-minded reformers in Washington.

I spoke to Kaufman and his chief of staff Jeff Connaughton a number of times while reporting my book on the Obama administration, and I always came away impressed with their knowledge of the financial system. So I was eager to read Connaughton’s own book, The Payoff, when it came out a few weeks ago, and I wasn’t disappointed. (The hard cover version is due out next week.)

Connaughton shares new details from the Brown-Kaufman crusade, which will be gripping to anyone interested in taming overgrown banks. But the book’s most important contribution, I think, is to tell the story of corporate influence over financial policymaking dating back several decades. You can pretty much feel the acid gushing into your stomach as you read it.

Connaughton has real authority as a narrator: He worked in a succession of investment banking jobs after earning an MBA at the University of Chicago in the 1980s. After Stanford Law School and a stint in the White House counsel’s office in the mid-1990s, he spent 12 years raking it in as a lobbyist, most of them as a partner at Quinn Gillespie & Associates, one of the most connected firms in town. When Connaughton condemns the revolving door, he’s a million miles from innocent, but he certainly knows what he’s talking about.

Some of the most eye-opening passages in the book draw on this body of knowledge. For example, despite having written about economic policy for over a decade, I’d never heard the term “Blob” before—a reference to the Wall Street-regulator industrial complex that governs our financial system. Connaughton dissects it with the practiced hand of a med-school anatomy instructor: