While teaching previsualization at the American Film Institute in 1993, Katz suggested to producer Ralph Singleton that a fully animated digital animatic of a seven-minute sequence for the Harrison Ford action movie "Clear and Present Danger" would solve a variety of production problems encountered when the location in Mexico became unavailable. This was the first fully produced use of computer previsualization that was created for a director outside of a visual effects department and solely for the use of determining the dramatic impact and shot flow of a scene. The 3D sets and props were fully textured and built to match the set and location blueprints of production designer Terrence Marsh and storyboards approved by director Phillip Noyce. The final digital sequence included every shot in the scene including dialog, sound effects and a musical score. Virtual cameras accurately predicted the composition achieved by actual camera lenses as well as the shadow position for the time of day of the shoot. The "Clear and Present Danger" sequence was unique at the time in that it included both long dramatic passages between virtual actors in addition to action shots in a complete presentation of all aspects of a key scene from the movie. It also signaled the beginning of previsualization as a new category of production apart from the visual effects unit.