What Happened To Steve Carey?
Like the two aforementioned characters that left in Season 8, John Carroll Lynch was written out by divorcing Mimi and moving away. He made one return after his tenure as main credit status ended.
What happened to Craig Ferguson (Mr. Wick)?
According to Craig Ferguson, despite having great friendships with all the cast/crew, he grew really tired of doing the show as he was not able to professionally develop. his disappearance in the final season was the result of him writing and directing the film "I'll Be There". In his book, Craig Ferguson noted "I was being used less and less. Sometimes they would just pay me to stay home and not do anything else, which sounds fantastic but it doesn't do much for your ego."
Christa Miller decided to leave the show to take a recurring role on her husband's new show Scrubs. Her character was written out by falling in love with an Air Force officer during the course of a week and then getting married and moving to Guam where he was stationed.