Dr. John is the stage name of Malcolm John Rebennack Jr. (born November 21, 1940), a colourful pianist, singer, and songwriter, whose music spans, and often combines, blues, boogie woogie, and rock and roll.
Born in New Orleans, Louisiana, his musical career began as a session musician in New Orleans in the 1950s. Early in his career he also played guitar and was often known as Mac Rebennack. He switched to the bass, and then the piano after his left ring finger was injured by a gunshot, while he was protecting his bandmate, Jesuit High School classmate, and longtime friend Ronnie Barron. Professor Longhair was an important influence on Rebennack. Rebennack gained fame beginning in the late 1960s and early 1970s, with music that combined New Orleans-style rhythm and blues with psychedelic rock and stage shows that bordered on voodoo religious ceremonies, including elaborate costumes and headdress. For a time he was billed as Doctor John, The Night Tripper. The name "Dr. John" came from a legendary Louisiana voodoo practitioner from the start of the 19th century.

He is perhaps best known for his 1973 hit song, "Right Place, Wrong Time", which reached #9 on the Billboard Hot 100. He was also a prominent session musician at this time, playing piano, for example, on the popular Carly Simon and James Taylor duet of "Mockingbird". He also contributed the song "More and More" to Simon's Playing Possum album. Dr. John has also done vocals for Popeyes Chicken & Biscuits' "Luv dat chicken..." jingle, as well as the theme song ("My Opinionation") for the early-1990s television sitcom Blossom. A version of "Do You Know What It Means To Miss New Orleans" with Harry Connick, Jr. was released on Connick's album 20 and VHS Singin' & Swingin' in 1990. Dr. John also contributed to the 1996 cover version of Lou Reed's Perfect Day with, amongst others, Bono and Tom Jones. His movie credits include Martin Scorsese's documentary The Last Waltz (in which he joins The Band for a performance of his song "Such a Night") , the 1978 Beatles inspired musical "Sgt. Pepper's Lonely Hearts Club Band", and Blues Brothers 2000 (in which he joins the fictional band The Louisiana Gator Boys to perform the songs "How Blue Can You Get" and "New Orleans"). He also wrote and performed the score for the film version of John Steinbeck's "Cannery Row" released in 1982.