VIDEO: Watch Neil Patrick Harris' 'Shocking' Final Appearance on LETTERMAN

Neil Patrick Harris made his 17th and final appearance on CBS's LATE SHOW WITH DAVID LETTERMAN earlier this week. Watch his "shocking" appearance below!

Harris was most recently seen on the big screen starring opposite Ben Affleck and Rosamund Pike in David Fincher's critically-acclaimed feature film, "Gone Girl." he garnered multiple Emmy and Golden Globe award nominations for his role as Barney Stinson on the hit television series, "How I Met Your Mother," and he won an Emmy for his guest-starring role on "Glee" in 2010.

He also recently starred in the title role of "Hedwig and the Angry Inch" on Broadway, earning the 2014 Tony Award for Best Actor in a Musical. Harris served as host of the 61st and 65th Primetime Emmy Awards, as well as the 63rd, 65th, 66th and 67th Tony Awards, for which he won four Emmys. Most recently, Harris added the title of author to his list of accomplishments with the release of his autobiography from Crown Publishing, Neil Patrick Harris: Choose Your Own Autobiography. He recently served as host of the Academy Awards.