That night, Conan realizes how the murder was done and who the culprit is. The next day, he drops a hint for Kogoro by spilling ketchup on a food cart which creates an evenly spaced ketchup stain on the floor, miming the victim's blood stain.

Kogoro and Conan are taken by Ran and Sonoko to a Rooster Festival at the Ranburi Shrine. Ran and Sonoko sneak off to have their love fortunes predicted. Sonoko reads Ran's fortune which strongly suggests her to be feminine and avoid mannish conducts. Sonoko is then robbed by a man wearing a hyottoko mask who flees with her purse towards Ran. Ran, hesitant by her love fortune, does not incapacitate him with karate and allows him to escape. Kogoro explains the man has been dubbed as the Rooster Man and is a serial robber at Rooster Festivals. Ran and Sonoko takes Conan with them to visit the festival again to have their love fortunes retold. A woman's scream is heard and they discover that the Rooster Man was spotted and stabbed a man before escaping.