In the 1950's, science fiction writer Isaac Asimov, under the pen-name Paul French, wrote a series of six novels for children known as the Lucky Starr series, which takes place in the future during a time when Earth and Sirius are on the brink of war.http://en.wikipedia.org/wiki/Lucky_Starr_series
The protagonist of the series is a space captain named David "Lucky" Starr.
His faithful sidekick is named John Bigman.
In the first book, titled David Starr, Space Ranger, Lucky Starr is engaged in a mission on Mars. Starr is stunned by Martians and later wakes up on a farm. Starr uses the alias Bill Williams.
Later he looses control of his car and crashes into a cavern. In the cavern he meets Martians who give him a mask which enables him to return to the farm.
Followers of the "Paul McCartney is dead" mythos will recognize many elements here:
The replacement is believed to be a man named William who goes by Bill.
In June of 1966, McCartney bought a farm in Scotland. Retreating to the farm after the breakup of The Beatles is thought by PID-believers to be "uncharacteristic of Paul. It is William returning to his former life."
It is believed that McCartney died in a car crash.
The Beatles rose to fame in Liverpool while regularly playing at the Cavern Club. (Ancient Egyptians mythology states that the sun, as Khepri the Beetle-Headed god, emerged from the Cavern of Mystery in the East each morning).
Many PID-believers state that the replacement wears a mask.
The second book introduces an antagonist named Dingo, which also brings to mind Ringo.
Dingo has a long nose and scar on his upper lip.
Dingo is ordered to kill Starr and make it look like an accident.
Starr and Dingo engage in a duel to the death.
Starr uses his alias Bill Williams again, as well.
More common elements here, in that in December 1965, McCartney was (allegedly) involved in a moped accident, which left a visible scar on his upper lip.
In the third book, Lucky Starr and the Oceans of Venus, we are introduced to two new characters, Mel Morris and Lou Evans.
They spend a lot of the book in a submarine, and the plot revolves around mind control.
The mind control device is contained in a rectangular computer concealed in its metal carrying case, much like a briefcase.
In order for the antagonists to test if the mind control is working on Starr and his companions, they are made to think of mustaches.
More elements of Beatles lore? Yep.
The Beatles body guard, equipment manager and good friend was Mal Evans. He was killed by police men in 1976, and it is believed the manuscript to the revealing book he was writing on his days with the Beatles is in a briefcase of his.
In this Asimov book, Evans sends a political message under Mel's name that causes an uproar, so we've got them essentially under one name.
Believers of PID state that the reason The Beatles suddenly all decided to grow mustaches in November of 1966 was because the replacement grew one to hide his surgery scars, and the other three grew them so that he wouldn't stand out.
Then of course there's the Yellow Submarine.
Book four is pretty innocuous.
In book five, Lucky Starr and the Moons of Jupiter, we meet a Sirian spy - a robotic German Shepherd named Mutt. The other proposed last name of McCartney's replacement is Shepherd.
In the final book, Lucky Starr and The Rings of Saturn, we meet a Sirian councilman named Yonge. Yonge pleads for the life of John Bigman, as the other Sirian officers are about to execute him.
The American DJ who went live on the air and discussed the "Paul is dead" rumor in October 1969 is none other than Roby Yonge. Yonge was immediately fired.
In this book, Starr has also since learned the name of another Sirian spy... Jack Dorrance. Whom Starr chases into the rings of Saturn.
In December 1974, Paul McCartney approached Isaac Asimov and asked him if he could write the screenplay for a science-fiction movie musical.
McCartney had a vague idea for the plot and a small scrap of dialogue; he wished to make a film about a rock band whose members discover they are being impersonated by a group of extraterrestrials.
The band and their impostors would likely be played by McCartney's group Wings, then at the height of their career.
Intrigued by the idea, although he was not generally a fan of rock music, Asimov quickly produced a treatment of the story. He adhered to McCartney's overall idea, producing a story he felt to be moving and dramatic. However, he did not make use of McCartney's brief scrap of dialogue, and probably as a consequence, McCartney rejected the story. The treatment now exists only in the Boston University archives.