Conversation so far:
What inspired the album Sgt. Pepper's Lonely Hearts Club Band?
An LSD trip inspired the album.
Are there any other interesting aspects about this article about Sgt. Pepper's Lonely Hearts Club Band?
In 1987, Anthony DeCurtis of Rolling Stone described Sgt. Pepper as the album that revolutionized rock and roll.

Question: What was the concept behind the album?
Self-contained rewrite: What was the concept behind the album Sgt. Pepper?