How the hell did four guys, from a city on the Northwest Coast of England, come to rule the world? I can not imagine what life would have been like without them. Can you?

How would the current economic state or all of the sorrows of the world compare to going through life never hearing "She Loves You" or "A Day in the Life"? Instead, we were able to live vicariously through a story that would make a great novel (if someone ever chose to write it as such). It has everything you need: desire, early failures, bleak moments, heartbreak, love affairs, dragon women and helpless maidens, martyrs, incredible characters-some dark and some light- coming and going just when they were most needed, insecurity and loyalty, triumph against all odds, the world held in the sway of four men who changed it all, a breakup that was viewed with more despair than Charles and Diana and-finally-four figures, four separate Phoenixes, stumbling to their feet and learning for the first time how to stand up without their three mates at their side. The intention of this book is to capture some of that story with a focus on the evolution of the bass playing of Paul McCartney. The book's genesis was a website devoted to his bass guitar work (still online at www.alstrand.com) but it became clear that any discussion of one aspect of the Beatles leaves the rest of the story wanting. For example, to talk only about McCartney's most famous bass line-the one in "Come Together"-ignores the innovative drumming of Ringo Starr, the swampiness of Paul's electric piano, the quality of John Lennon's voice, and the mere fact that he is saying "shoot me" at the start of each instrumental riff. To talk about one thing, you have to talk about it all.

Writing this book, I soon realized, was like riding on an emotional roller coaster. Pull out an old Beatles' chestnut and listen closely to it with the intention of explaining it to someone else and you'll see what I mean. In my case, maybe something about the structure of the arrangement would strike me as brilliant and I'd grapple for words to describe it. Words that did not make me sound like a wide-eyed, throat-gurgling, gob-smacked fanatic. Which I am, but I do try to hide it in these pages.

The songs that I had the most fun with were "She Loves You," "A Day in the Life," "Hey Jude," "Come Together" and "I Want You (She's So Heavy)." Each song presents itself as a well-orchestrated masterpiece, complete in every way. To me, the Beatles were such an incredible team-such a tight unit-that whatever an individual did had an impact on the larger unit. In the early days, the group would generally run their songs through what I call the Beatles Machine. A song would go in with chords and melody and come out a full-fledged Beatles song.