The four members of Milky Holmes are going on a study tour. While soaking in the hot springs among snow monkeys, alarms interrupt the relaxing environment! It was the work of the Thief Empire. A fierce battle between Milky Holmes and the Thief Empire begins, with both sides using their Toys (special powers). Furthermore, with the arrival of the Genius 4, a three-way fight occurs! In the midst of battle, a violent lightning strikes from the sky. Struck by the lightning, the four Milky Holmes girls lose their abilities.

A special program of Tantei Opera Milky Holmes produced by the staff of the TV series. After some pushing by Irene and her father and a lack of support otherwise, Kokoro stubbornly quits her job as a police detective to become an idol. She soon finds the idol life draining and starts to miss her old detective life. When Henriette notices Sherlock's loneliness without her, she stages a statue theft in order to convince Kokoro to return to the force. (Source: AniDB)

Milky Holmes is a detective team composed of four girls who descended from famous detectives and possess supernatural powers known as "Toys". In this alternative world, instead of losing their Toys and becoming worthless students, they are on the path to becoming successful detectives. Under the guidance of Kobayashi Opera, they work to solve mysteries. (Source: AniDB)

Fans of the Milky Holmes detectives, Kazumi and Alice, decide to form their own detective unit, calling themselves "Feathers." (Source: ANN)