Higashino Keigo Whose Is the Cuckoo's Egg?

Kazami strives to be a top skier like her father Hiromasa, but there is a secret hidden behind their relationship. A threatening letter arrives.

A bus that Kazami almost rode explodes, sending a man named Kamijo to the hospital. Kazami starts to question herself after seeing Shota injured.

Yuzuki asks Kazami questions about her late mother. Kazuma and Shingo get chosen to go to a training camp for cross-country skiing.

Hiromasa realizes Kazami could be related to Kamijo's son Fumiya after learning that he has leukemia. Kazami makes a shocking discovery in Maebashi.

Hiromasa learns about the sad events in Hiroe's life that led to his wife's decision to raise Kazami. Fumiya receives a visit from Hiromasa.

The bus bombing incident had appeared to be a settled matter, but another dark element comes into play. Kazami receives a call to come out to a cabin.