When the original Jurassic Park was released in 1993 it revolutionized film by incorporating mechanical dinosaurs and ones created on computers. More than two decades later, the new Jurassic World used even more CGI firepower than before. But there was one scene with an apatosaurus that still needed a tactile dinosaur the actors could interact with. In the clip above, from the movie's upcoming Blu-ray release, director Colin Trevorrow explains why that dino was necessary and how the crew at Legacy Effects brought him to life.

Jurassic World hits stores on DVD and Blu-ray tomorrow.