Movies at Miller: Haunted Mansion at Miller Outdoor Theatre in Houston is a free Halloween screening of the 2023 Disney horror comedy inspired by the classic theme park attraction. Set in the leafy green space of Hermann Park, Miller Outdoor Theatre is a laid-back open-air venue, so you can settle in under the stars and enjoy a spooky film with the whole crowd. It's free, it's outdoors and it's a fun way to celebrate the holiday.