The stories behind the Johnny Cash song "Ring of Fire."

A behind-the-music look at the song "Jackson," released by Johnny Cash and June Carter in 1967.

The stories behind the song "A Boy Named Sue," written by Shel Silverstein and made famous by Johnny Cash.

The song "Sunday Morning Coming Down," written by Kris Kristofferson and performed by Johnny Cash, is explored. Interviewees include Kristofferson.

Johnny Cash's interpretation of the Nine Inch Nails song "Hurt" is examined, with Trent Reznor lending insight.

A portrait of Dolly Parton that centers on the inspiration and stories behind her songs. The premiere puts the focus on her 1974 track "I Will Always Love You," which was later recorded by Whitney Houston.

The finale centers on the 1978 song "It's All Wrong, But It's All Right," penned and recorded by Dolly Parton.

After the first singles on her debut record don't get any traction, Sheryl finds success with a powerful statement about finding a partner who can truly be her equal.

Following years of singing backup for other artists and contending with envious collaborators, Sheryl proves her autonomy with a hit that solidifies her position as a musical powerhouse who answers only to herself.

Sheryl taps into her personal life for inspiration, leading to an intimate song about a past relationship and creating speculation over her unnamed muse.

Inspired by a trip to war-torn Bosnia, Sheryl writes this song, which is later recorded by Johnny Cash, and ultimately ignites her interest in recording country music.

The anthem ranked by Rolling Stone as one of the "500 Greatest Songs of All Time."

Blondie's hit single from the 1978 album "Parallel Lines," which sold over 20 million copies.

The Grammy-nominated song featured in the film, "American Gigolo."

The first song to feature rapping that went all the way to #1.

Lindsey's unique meshing of violin and electronic music once left the music industry baffled, but her perseverance and creative use of YouTube as a promotional tool helps her reach a massive audience.

As Lindsey's music continues to find bigger audiences, her videos allow her to express the passion for dance that she had put on the shelf.

The song "Travelin' Thru," written by Dolly Parton for the 2005 film "Transamerica," is explored.

A behind-the-music look at Dolly Parton's 1980 song "9 to 5."

Cash tries to find his voice; and a tape-recorder mistake inspires a riff.

Stories about the 1973 Dolly Parton tune "Jolene" are recounted.

Anecdotes are related about the 1971 song "Coat of Many Colors."