The Dirt: Confessions of the World's Most Notorious Rock Band is the story of the four young men who would join to create the musical group Motley Crue. The book provides background on the four men to provide the reader with insight on the personal motivations driving each of them toward their career with music.

Motley Crue is composed of four young men: Nikki Sixx, Tommy Lee, Mick Mars and Vince Neil. Their paths began in Indiana, Idaho and California and converged in Los Angeles in the early 1980s to create a heavy metal group that rises to global notoriety and success. Along the way, the men exploit their celebrity by abusing alcohol, drugs and women. Consequently, the personal relationships they form are flawed and are not able to sustain or be sustained.

Nikki comes from a completely dysfunctional family with an absent father and alcoholic mother whose behavior runs from complete disinterest to stifling control. Nikki finds his only stability on the farm of his grandparents in Idaho but he realizes that Los Angeles is where he needs to be to start his musical career and moves there as a young boy on his own. Mick Mars travels the farthest to launch his dream, when his family moves from Indiana to California to help his sister's respiratory condition. Mick lives the estranged life of a rock musician and eventually meets Nikki in a music store and half of Motley Crue is formed.

Vince Neil is raised in the gang-ridden, inner city neighborhoods of Compton, California, a suburb of Los Angeles. Vince and his family are terrorized by gangs until the family moves to Glendora and he becomes a juvenile delinquent as he also becomes more heavily involved in music. Vince encounters Tommy Lee, who is obsessed with playing the drums and the two become friends, establishing the other half of Motley Crue.

The group struggles to make a living while hoping for a record deal when they are discovered one night while playing a gig at the Whisky A Go-Go in Hollywood. From that point, the boys make a record, go on tour and rise to the top of the charts in rock music. This newfound celebrity and wealth is seen as a ticket to excess as well as success and all the boys abuse heavy drugs and alcohol. They also have unlimited, indiscriminate sexual encounters with girls and become famous for their exploits before and after concerts as well as in hotel rooms and even in their own homes.

In spite of the meteoric rise to fame, each of the boys longs for stable home lives but their lifestyles prevent any sort of long-lasting relationships or stability. Each of them suffers personal tragedies including death and estrangement in core relationships but they persevere and maintain through it all because of their love of the music.