This article presents a compelling case study that underscores the importance of a thorough differential diagnosis for headaches. A 35-year-old female patient reported sharp headaches that occurred exclusively when she was watching movies in a theater. She also suffered from more frequent, dull cervicogenic headaches related to a past whiplash injury. Initial chiropractic treatment, including cervical manipulation, successfully resolved her general neck pain and the dull headaches, but the "theater headaches" stubbornly persisted. This prompted a referral to a colleague with a DABCI nutrition specialty. The key to the puzzle was uncovered through food sensitivity testing, which revealed allergies to gluten and corn. The specialist then connected this to the patient’s movie-going habit: consuming a large soda (with high-fructose corn syrup) and a large popcorn. When the patient attended a movie without eating popcorn or drinking a Coke, she remained completely headache-free. This case serves as a powerful clinical reminder that a patient can suffer from multiple types of headaches with distinct triggers. It highlights the necessity of looking beyond the musculoskeletal system and considering factors like diet and food sensitivities, demonstrating the value of specialization and collaboration within chiropractic practice.