John Ritter Jack Tripper Actor Joyce DeWitt Janet Wood Actor Priscilla Barnes Terri Alden Actor Richard Kline Larry Dallas Actor Jenilee Harrison Cindy Snow Actor Don Knotts Ralph Furley Actor Sue Ane Langdon Guest Star Herman Poppe Guest Star Michael Ross Executive Producer Bernie West Executive Producer George Burditt Executive Producer Martin Rips Producer, Writer Joseph Staretski Producer, Writer George Sunga Producer Dave Powers Director