|The Grand Yokohoma Gorge of Fear|
|Japanese Title|| 恐怖のグランドヨコハマ峡谷|
(Kyōfu no Gurando Yokohama Kyōkoku)
|Airdate||December 17, 2010|
|Previous Episode||An Unsuitable Job for Milky Holmes|
|Next Episode||The Return of Milky Holmes|
The Grand Yokohoma Gorge of Fear is the eleventh episode of the first season of Tantei Opera Milky Holmes.
As Milky Holmes go their separate ways, Henriette becomes furious with disappointment and goes on a crime spree as Arséne. G4 briefly visit Sherlock, working at a ramen shop, before heading off to face Arséne. As Sherlock visits the other girls, Henriette hosts a broadcast saying Arséne has kidnapped her, willingly putting herself into a trap over Yokohama Gorge which could send her to her death. When G4 are defeated by the Gentlemen Thieves, Sherlock gathers together Milky Holmes and are given a ride by Irene to the gorge. While the others hold the thieves back, Sherlock dives after Henriette as she falls, which activates her Toys, along with the others. However, Henriette than changes into Arséne, revealing a plan she has wanted to fight against Sherlock at her true potential.