The Million Dollar Quartet weren't a group in any normal sense, but were initially more of a photo opportunity and then a freewheeling after-hours jam session between Elvis Presley, Carl Perkins, Jerry Lee Lewis, and Johnny Cash that took place at Sam Phillips' Sun Studios in Memphis on December 4, 1956. It was formally a Carl Perkins session, with Jerry Lee Lewis sitting in as the piano player. At some point Presley and Cash stopped by to observe, and Phillips, recognizing a photo op when he saw one, called a local news photographer, who snapped a photograph of the four musicians gathered around a piano.The picture ran the next day in the Memphis Press-Scimitar with the caption"The Million Dollar Quartet." The Perkins session morphed into an impromptu jam after the photographer left, and Phillips fortunately kept the tape running as the four musicians ran through some 40 songs ranging from gospel spirituals and country standards to covers of Bill Monroe and Chuck Berry songs (or in other words, most of the ingredients that went into the creation of rock & roll). There is some debate as to whether Cash was actually there for the jam (he claims he was in his autobiography), and most of the singing is Presley's, but the joyous spontaneity and the fly-on-the-wall feel of the occasion makes these tapes fascinating listening.The first bootlegs of the session appeared in 1980, with Charly Records officially releasing a 17-song set in 1981. More tapes were subsequently found (in all, three reels have been located to date) and Charly issued a double-LP set with 41 tracks from the session in 1987. The caption from the publicity photo, the Million Dollar Quartet, has stood the test of time and is now forever linked to these four musicians and to one of the most famous jam sessions in the history of pop music.