He says he created the effects with his protege, Ray Harryhausen, who as a teenager had watched King Kong over and over again, looking up to O Brien as his idol Harry House, and went on to create some of the most iconic visual effects in movie history soon after Mighty Joe Young Harry House and worked on a movie called The Beast from 20,000 Fathoms, about a giant monster that wreaks havoc after being awakened from atomic bomb testing.
他說,他和他的門徒雷-哈里豪森一起創作特效,他在少年時代就反覆看《金剛》,把奧布萊恩看成是他的偶像哈里豪斯,在《壯志凌雲》之後不久,他就創作出了電影史上最具代表性的視覺特效,並參與了一部名為《兩萬英尺的野獸》的電影,講述的是一個巨大的怪物從原子彈試驗中被喚醒後大肆破壞的故事。