Richard reviews the events that took place before the murder of Stefan van Croven and discovers everyone in the villa has a motive to kill because van Croven has been lying and blackmailing them. Conan finds a ladder in a closet and cellophane tape stuck to the curtain rack to discover the trick used in the lock room murder. Conan stuns Richard to reveal that by using the film projector and cellophane tape stuck to the door lock, anyone can be the murder. But points out the murderer is Torakura's student, Jonathan Tradonio, because of a bad lie he told before the body was found.