Brian "Kato" Kaelin is a blonde surfer dude type of guy. He was probably the funniest part of the whole O.J. Simpson trial. His nickname Kato comes from the Bruce Lee movie/television show The Green Hornet (oddly enough O.J.'s children named their dog "Kato" also).
Kato is well known as a professional freeloader. Living rent free for years in O.J.'s guest house. His only duties were as an occasional babysitter to the Simpson children.
He was a crucial witness in the O.J. trial. But his behavior on the stand was so strange prosecutor Marsha Clark began to treat him as a hostile witness, and frequently accused him of "changing his story."
Kato rode his new found fame into both a radio show and a talk show (both were short lived). His final moment in the sun was appearing on the cover of Playgirl magazine a few years ago. He briefly toured as a lecturer where he gave his "The 16th Minute" speech, discussing what happened after his 15 minutes of fame ended.
Kato eventually ended up becoming truly wealthy as a side effect of the O.J. Simpson trial, because he was awarded 15 million dollars in damages because the National Examiner ran a headline that said "Cops Think Kato Did It." He won that lawsuit in 1999, and he hasn't done very much since then.
In most of these films he only has bit parts, or plays himself. In addition to these film appearances he has had many one time television roles, where he usually played himself. He shot a pilot in 2002 for his own show, "House Guest," but no one ever picked it up for regular production.