Doctor Who is a British science-fiction show that premired in 1963 and ran until 1989, it went back into production in 2005 and still runs today. It follows the adventures of an ailen time-traveler known as "The Doctor". The Beatles were fans of the series and John Lennon even posed with a Dalek (a race of villians featured on the show.)
In the episode of it entitled "The Chase", the main characters all watched a recording of the Beatles performance of Ticket to Ride.
Another Beatles song was used in the 1967 episode Evil of the Daleks. In it, Paperback Writer was heard playing in the background of a café.
The Second Doctor, the Third Doctor, and Jo Grant all quoted the song "I Am the Walrus" in the 1973 anniversary episode The Three Doctors.
In the 1985 episode Revelation of the Daleks, the DJ had posters of the Beatles in his studio.
In the 1987 episode Remembrance of the Daleks (Set in 1963) the mains character Ace was seen walking into a bar where Elvis Presley music was playing, and promptly switching it to the Beatles' Do You Want to Know A Secret?. A Taste of Honey was heard later in the episode. These songs were initially cut from the originalDVD release and were replaced by covers by other artists but the story has since been rereleased and the tracks were reinstated.
In the 1989 episode Ghost Light, the Seventh Doctor stated to his companion Ace "It's been a hard day's night."
Doctor Who was cancelled that same year, in 1989, but references continued to occur in spin-off material.
In the 1993 book The Left-Handed Hummingbird, Ace was seen saving the Beatles from an assassination attempt at their Let it be roof-top performance.
In the 1996 book Who Killed Kennedy, James Stevens got a Beatle to pose with him and his royal wife at their wedding, thus making it a front-page story.
The 1997 book The Devil Goblins from Neptune suggests that the Beatles didn't break up in 1970 and instead kept performing.
In the Short Trips story "Gone too soon" published in 2000, the Sixth Dcotor was seen "jamming" with the Beatles in Hamburg.
The Beatles appeared in the Cavern Club in the 2007 Tenth Doctor comic story Signs of Life and the 2008 comic story The Time of My Life. The Tenth Doctor and Martha attempted to go the the Beatles' 1969 rooftop performance in Black Death White Life.
In the 2010 video game City of the Daleks, The Eleventh Doctor and Amy discussed which Beatle they would like to meet. Amy stated "John Lennon" and the Doctor replied "Why does no one ever say Ringo?"
In the 2011 episode The Wedding of River Song, the Eleventh Doctor listed "...Join the Beatles..." along with other things that he could do before he died.