Home People John T. Kretchmer John T. Kretchmer movies John T. Kretchmer movies John T. Kretchmer Movies (6) Bad Girls from Valley High (2005) As Director. He was 50 years old Jurassic Park (1993) As First Assistant Director. He was 38 years old Welcome Home, Roxy Carmichael (1990) As First Assistant Director. He was 36 years old Flatliners (1990) As First Assistant Director. He was 36 years old The Naked Gun: From the Files of Police Squad! (1988) As First Assistant Director. He was 34 years old Silver Bullet (1985) As Assistant Director. He was 31 years old