 During his time of employment at the Ocean Institute , Hillenburg attended an animation festival and determined that he wanted to pursue a career in that field . He had already been planning on returning to college for a master 's degree in art . Instead , he chose to study experimental animation at the California Institute of the Arts . His thesis film , Wormholes , is about the theory of relativity . It was screened at festivals , and at one of these , Hillenburg met Joe Murray , creator of the popular Nickelodeon animated series , Rocko 's Modern Life . Murray was impressed by the style of the film and offered Hillenburg a job . Hillenburg joined the series as a director and later , during the fourth season , he took on the roles of producer and creative director . 
