?Saturday Night Live? star Kenan Thompson began his time in SNL in 2003. According to UPROXX, he is the show?s longest-running cast member. During an interview with Ellen DeGeneres, Thompson was asked how long he would stay on the show. Thompson said he hasn?t even thought about leaving the show and said he would definitely be on until 2020. He said: ?I can?t see myself just walking away from it like that.?