During filming, KITT was voiced by a script assistant, with voice actors recording KITT's dialog later. David Hasselhoff and original series voice actor William Daniels first met each other six months after the series began filming. KITT's evil twin is KARR, whose name is an acronym of Knight Automated Roving Robot. KARR was voiced first by Peter Cullen and later by Paul Frees in seasons one and three, respectively, of the NBC original TV series "Knight Rider". A 1991 sequel film, "Knight Rider 2000", centered on KITT's original microprocessor unit transferred into the body of the vehicle intended to be his successor, the Knight Industries Four Thousand (Knight 4000), voiced by Carmen Argenziano and William Daniels. Val Kilmer voiced KITT in the 2008–2009 "Knight Rider" series.