An inside look at how Toyota, Nike, and SV Angel keep on growing.

By Geoff Colvin, senior editor-at-large

FORTUNE -- Einstein observed that no matter how smart you are, or how long you ponder, you can never be sure how a watch works unless you look inside. He was making a point about understanding the universe, which we'll leave to physicists and just note that it's the same with business. We can easily study a company or an industry from the outside, but we'll never really know how it works until we get inside. That's why, in this special package of articles, we're presenting examples of the classic deep Fortune story, going inside three companies to see how they really work.

Start with a dethroned king -- Toyota (TM), colossus of the global auto industry until just two years ago, when it was humbled by a confluence of crises. In "Toyota's Comeback Kid," auto industry authority Alex Taylor III reports from New York, Los Angeles, and Toyota City, Japan, explaining exactly how the quondam king intends to regain its throne and why its chances look good.

If you want to see into the future of marketing -- and you do -- there is no better place to look than Beaverton, Ore., specifically the Jerry Rice Building at Nike headquarters. Few fields have been disrupted by the infotech revolution as profoundly as marketing. Online advertising will exceed print advertising this year for the first time, says the eMarketer research firm. In "Nike's New Marketing Mojo," Scott Cendrowski reports from inside the Jerry Rice Building on why Nike (NKE) has slashed its ad budget (no Super Bowl commercial this year), where it's putting its marketing muscle instead (Twitter, Facebook, your phone), and what it means for the rest of us (lots).

Now proceed 600 miles due south to the heart of the infotech revolution, Silicon Valley. A new generation of potentially world-changing companies is being spawned there, and the man who invests in more of them than anyone else is Ron Conway, a figure little known outside the Valley. It turns out that to understand how Silicon Valley works today, you need to understand Ron Conway. Fortune's Miguel Helft explains the man and his methods.

How a watch works, once you figure it out, isn't all that interesting. How Toyota, Nike, and Silicon Valley work is extraordinarily interesting and more. It's important.

How it works

Toyota's Comeback Kid

Nike's New Marketing Mojo

A Silicon Valley startup's best friend

This article is from the February 27, 2012 issue of Fortune.