Details are given of a new advanced theory of mind task, developed to approximate the demands of real-life mentalizing in able individuals with autism. Excerpts of films showing characters in social situations were presented, with participants required to answer questions on characters' mental states and on control, nonsocial questions. When compared with control participants, adults with high-functioning autism and Asperger syndrome were most impaired in their ability to answer the questions requiring mind-reading ability. Although the present findings have implications for task modification, such naturalistic, dynamic stimuli are held to offer an important means of studying subtle difficulties in mentalistic understanding.