While stargazing at a playground, Sonoko directs her binoculars towards the city and witnesses someone lifting an arm in the shadow of a flowerbed. Sonoko brings Conan and Ran with her to investigate the scene of the alleged crime. The flowerbed is located in front of Sasaki Studio, and Sonoko explains the situation to studio director Hiroto and his assistant Rika. Hiroto believes Sonoko saw the arm of a mannequin. Sonoko and her friends decide to investigate the Yoshimura building next door, which has the same flowerbeds on its roof. Since Yoshimura is away on a business trip, they try to speak with his wife Nanae, but they're unable to find her...