Gwynne Gilford was pregnant during filming and the production team had to hide her stomach in most of the shots. That baby is now actor Chris Pine.
Dennis Christopher adamantly wanted to do the rooftop stunts, but the producers insisted on using a stuntman.
Horror of Dracula (1958) clips were used during the Dracula scene after Universal Studios denied permission for the filmmakers to use clips from Dracula (1931).
Chris Stein of the new wave group Blondie was the original choice to compose the soundtrack but his deal was canceled.