(CNN) -- The music video is almost iconic for the 1980s.
There's Billy Joel, dressed as a mechanic singing the praises of his "Uptown Girl," the nattily dressed supermodel, Christie Brinkley. The pair was a couple at the time, so of course Joel wrote the song for her, right?
Not so fast say two British writers.
Michael Heatley and Frank Hopkinson are the authors of the book "The Girl in the Song: The True Stories Behind 50 Rock Classics." In it they claim that Joel originally penned the hit tune for another beauty: model Elle Macpherson.
'I didn't think that was necessarily a sensational fact, but people are shocked by that," said Hopkinson.
According to the book, Joel met both Brinkley and Macpherson during a Caribbean vacation. The song was originally titled "Uptown Girls" and changed to the singular after things fizzled with Macpherson and Joel took up with Brinkley. She went on to appear in his video, they married in 1985 and divorced in 1994.
Hopkinson spoke with CNN about why fans are fascinated with the stories behind songs, the reasons some musical artists like to maintain the mystery and whether there will be a book about men who inspire songs.
CNN: How did you find the stories?
Frank Hopkinson: We did loads of research, on the internet, through old biographies, through cuttings agencies, pieces from Radio 4, broadcasts.
It's a whole gaggle of different sources. Very little of it wasn't already in the public domain. I think our job, our skill if you like, was assembling a variety of them.
CNN: What gave you guys the idea for the book?
Hopkinson: I was doing another book and I had to do some research on Leonard Cohen. I was researching the Suzanne story which is a sort of poem and there was a whole story about this woman who originally was an artist's wife in Montreal.
Cohen obviously fancied her and took a shine to her and she wasn't having any of it. He left and became a big star. He took the poem "Suzanne," he wrote and turned it into a song.
I read a story about how quite recently -- and she's had had quite a traumatic life -- she left Canada and had moved to California where she was working as a choreographer. She had had an accident and now she was homeless and living in the back of a truck.
It was very sad. If you go on the internet, there is actually a group that's the "Friends of Suzanne."
But in the song she lives on as this shining, hippie Bohemian who is celebrated in the song.
CNN: What is it about these back stories that are so interesting to fans?
Hopkinson: It's just amazing how things turn out. People are just fascinated to learn about the muses of these artists.
When you talk to artists, they like to lead you on. They'll say one thing and then change their minds.
There's a David Bowie song, "Life on Mars," which is about a woman called Hermione Farthingale and which is featured in the book. She left him and he was absolutely devastated.
A few years later he wrote "Life on Mars." In print he's said "I went out with her for three months," but we know for a fact he went out with her for a year because we've talked to her about it.
It's interesting how some artists like to create mystery.
CNN: Was there a story that was surprising to you?
Hopkinson: I was slightly surprised by (the story about) the Buddy Holly song "Peggy Sue."
Buddy Holly's friend was called Jerry Allison and I'd always thought that Buddy Holly wrote the song as a favor to his friend, like "I'll write a song about your girlfriend."
But Peggy Sue Gerron has written an autobiography ... and she's inferring that she was maybe closer to Buddy Holly than just being the girlfriend of his drummer.
CNN: Have you all considered a follow-up?
Hopkinson: There are only so many songs out there.
We've thought about the "Boy in the Song," but it's a different thing when men write about men.
There are obviously women writing about men and it would be quite interesting I think comparing the two.