A famous movie star and her body double show up at the same cabin Kogoro and family are spending vacation time at, but when a note and a mysterious illness seem to overcome the star, then Kogoro decides to begin searching it as a case. Is there something more than a mysterious suicide note though that could indicate murder?
The killer was Akiko Kinoshita's companion and body double Yoko Asanuma, out of jealousy since Akiko always got fame and recognization but she only got to play second fiddle to her at best.
Yoko first forged a letter in which Akiko said she was ill and wanted to commit suicide, then booked a room in the inn (which she knew of since she worked htere past-time long ago) and arranged so they'd spend the night there.
The following day, Yoko drugged Akiko and knocked her out when they were out skiing. She later took off her ski outfit and put a white kimono on her, burying Akiko in the snow, which would cause her a deathly hypothermia. Yoko then put Akiko's snow clothes, which included a full-face mask; this let her return to the inn unnoticed, and since then on she used her knowledge of the place to play the role of both women, tricking everyone into believing that Akiko was in their bedroom due to her "illness".
Later, the false letter containing info about Akiko's supposed "illness" was found, and everyone thought she had run away to kill herself. This was "confirmed" when her body was located in the snow.
