[1] By the age of 18, Hettema was studying music at California State University, Long Beach, with weekend employment in the wardrobe department at Disneyland.
[1] Hettema then worked with a number of Walt Disney Imagineering employees to develop attractions for a Beatrix Potter theme park in England.
Although this theme park never eventuated, these connections led to him working as one of three production supervisors on the opening and closing ceremonies of the 1984 Summer Olympics in Los Angeles.
[1][2] He joined as a line producer for an upcoming show at Universal Studios Hollywood; however, on his first day he was told the existing script was discarded and he would be required to start fresh.
This left Hettema and his team less than four and a half months to develop the Miami Vice Action Spectacular, prior to opening on July 4, 1987.
[1] Hettema's next project was to help design Back to the Future: The Ride, which was originally set to debut at Universal Studios Hollywood.
[1] Steven Spielberg tasked Universal Creative and the Totally Fun Company create a simulator ride concept based around Back to the Future.
[4] Islands of Adventure was subsequently developed featuring the intellectual properties of Dr. Seuss, Jurassic Park, Marvel Comics, Jay Ward Productions and Paramount Pictures.
While Hettema oversaw much of the park's design, he is credited with helping to invent the ride systems for The Amazing Adventures of Spider-Man and The Cat in the Hat.