The last episode of the series talks about the most important city in the States. Stories that go from the early 40s until today. Interviews with Rick Rubin, Emmylou, Chris Martin, LL Cool J and Barack Obama. And a real statement about what is happening with the studios business nowadays. The song 'I Am A River' is recorded during this episode.

Dave Grohl returns to his musical roots, while the Foo Fighters prepare to record at Seattle's Robert Lang Studio with Death Cab for Cutie's Benjamin Gibbard. Dave sets his focus on the Seattle music scene, mainly the grunge movement and its implications in American Rock Music. Interviews with Chris Cornell, Nancy Wilson, Bruce Pavitt.

Dave Grohl discusses New Orleans' unique music history with Dr. John, Allen Toussaint and Cyril Neville. The band records in Preservation Hall and also performs with the Preservation Hall Jazz Band. The song 'In the Clear' is recorded during this episode.

Los Angeles' highly influential position in rock history is examined. Pat Smear remembers the days of Germs, and visits legendary KROQ disc jockey Rodney Bingenheimer, owner of a 1970s Sunset Strip club that became the hub for the Los Angeles glam rock scene. Foo Fighters head to the desert to record their new song 'Outside', which features a solo from Eagles' guitarist Joe Walsh, at Rancho De La Luna, and in turn, Kyuss and the 1990s Palm Desert Scene is explored.

Foo Fighters prepare to record at the Austin City Limits Studio, with blues guitarist Gary Clark, Jr. In this episode is examined the roots of Austin's music scene, with interviews featuring Billy Gibbons from ZZ Top, and Roky Erickson from 13th Floor Elevators, who is considered one of the American fathers of psychedelic rock. Dave also chats with Terry Lickona, the executive producer of Austin City Limits. The song 'What Did I Do? / God As My Witness' is recorded during this chapter.

The band heads to Nashville, Tenn. Dave sits down with Dolly Parton, Tony Joe White, Steve Earle, Willie Nelson, Emmylou Harris and producer Tony Brown to discuss Nashville's musical influences and the Nashville sound. Foo Fighters prepare to record at Southern Ground studio, owned by country musician Zac Brown, who also guests on the song 'Congregation'.