A seven year old movie star by the name of Kazuki Kinukawa comes to the Mori office to try and find his mother who abandoned him at a church. His reasons are to tell his mother he will not give her any money now that he is famous. Conan is able to deduce Kazuki's mother is a hotel employee in Atami due to the old dirty postcards she sent him. Kazuki reveals that he remembered that his mother had a beauty mark near her breast. A freelance writer named Yushiro Kamoshita checks into the hotel as he plans to find Kazuki's mother and interview her to confirm whether Kazuki's father was truly a murderer. Later that day, Kamoshita is strangled to death but managed to take a picture on his cellphone during the attack. The picture reveals that a woman with a beauty mark near her breast is the murderer. The police gather three female employees with no alibi during the time of the murder; Each of them has a beauty mark but none of them are near the breast.