Don Knotts' final appearance as a regular cast member, during the first five seasons. He returned as a guest star for five more episodes, in the final three seasons. In order, they are first, The Return of Barney Fife (1966). Second is The Legend of Barney Fife (1966). Third is A Visit to Barney Fife (1967). Fourth is Barney Comes to Mayberry (1967). Fifth and last is Barney Hosts a Summit Meeting (1968).
Opie Taylor (Ron Howard) asked Andy Taylor (Andy Griffith), "Can I get one of those jerseys with the numbers on them? They're good for football. You never have to wash them." During the previous season, Opie wore a jersey with the number 14 in season 4's Andy and Opie's Pal."
It's disappointing that Barney's final episode didn't give him any kind of goodbye.