CHICAGO - The new stage musical "Million Dollar Quartet" tells the story of the impromptu 1956 jam session of Elvis Presley, Jerry Lee Lewis, Carl Perkins and Johnny Cash.

What it doesn't divulge is an Elvis-related mystery that continues to confound historians as well as the show's playwrights.

Only five of the six "Quartet" cast members existed in real life: the singers plus Sun Studios founder Sam Phillips, who preserved the magical '56 meeting in Memphis by flipping on his tape recorders. It's that sixth character, Dyanne, Elvis' girlfriend, who was created because no one knows what happened to the young woman who actually did appear on Elvis' arm that day.

"I think she's one of the few Elvis girlfriends to completely vanish into the ozone," said Colin Escott, who co-wrote the play with Floyd Mutrux and who is the author of "Good Rockin' Tonight: Sun Records & the Birth of Rock & Roll."

In fact, unlike other women who told (and sometimes sold) their story of time with Presley, the woman that day - believed to be named Marilyn Evans - has never appeared in any article, fanzine or made-for-TV movie, said Peter Guralnick, author of an authoritative two-volume Elvis biography ("Last Train to Memphis" and "Careless Love"). Only those there that day have provided the scant information about her: Evans was 19, performed as a showgirl at Las Vegas' New Frontier Hotel and Casino and dated Elvis only for a few weeks.

"After that, it's a mystery," said Guralnick, who added that Perkins, before his death, insisted that the woman had a different name.

Lewis, the only living member of the quartet, is touring Europe this week and could not be reached for comment.

Either way, a woman surely was there at Sun: a female voice, believed to be hers, can be heard on the recordings from that day as she suggests a song title to the singers. And while there is an iconic photo from that session, which shows the quartet clustered around a piano, another version - believed to be the uncropped original of the famous photo - features a woman, believed to be Evans.

And because of that photo, "Dyanne" was born.

Escott said he included her because she helps move the story along, but he changed the name for legal reasons, just in case Evans is alive, a fact that would prevent producers from telling her story without her permission.

"Given that lawyers govern everything these days, they said, if you don't know where she is, (then) we had to create a fictitious character."

Not that he's opposed to her being found - Escott said he'd love to know what happened to her. (If alive, Evans would be 70 or 71.) Given that Evans has kept quiet this long, it seems doubtful she will raise her voice any time soon.

Finding her is nearly impossible as well, given her common name, the fact that most entertainers did not stay in Las Vegas and the lack of employment records from that period. (Last year, developers demolished the New Frontier.) Several Las Vegas historians, including a retired showgirl who performed in Vegas in 1956, told the Chicago Tribune they haven't a clue where Evans went.

"The name just doesn't ring a bell," said Betty Bunch, who danced at The Sahara, just down the Strip from the New Frontier, and who lectured on that era of Vegas' past.

"That was the year before it got really big out here, so I should remember her, but I don't."

Someone must, of course, know something, so if you're out there and reading this, give us a shout.

The Million Dollar Quartet needs your two cents.

(c) 2008, Chicago Tribune.

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