If you thought the T-Rex looked scary on screen, apparently things weren’t all that different during filming either. Thanks to the rain, the animatronic T-Rex would frequently short circuit and ‘come alive’ of its own accord. Producer Kathleen Kennedy has said: “We’d be, like, eating lunch, and all of a sudden a T-Rex would come alive. At first we didn’t know what was happening, and then we realized it was the rain. You’d hear people start screaming.”