Shortly after completing his education, he moved to New York City and began a career in retail at Tower Records. During that time, he worked on several projects, but Walker was unable to find much success until 1991, when he completed the script for "Seven". Walker decided to move to Los Angeles to sell his screenplay. There, he personally contacted screenwriter David Koepp, who showed the script to executives at New Line Cinema, who ended up purchasing the rights to it. The film, however, took nearly three years to begin production. "Christmas Vacation" director Jeremiah Chechik was originally chosen to direct the optioned film but he asked for a number of modifications, including the changes to the ending, particularly the removal of the head in a box scene. Walker continued reworking the script but the film got passed around in Hollywood. The project finally went ahead when David Fincher agreed to direct the film after he read the original draft, which was accidentally sent with the ending intact.