Room 401

is the forty-second episode of Kamen Rider Ryuki. It is the second of the four-part arc of Kamen Rider Imperer.
==Synopsis==
*Mitsuru accepts both sides' offer to ally with them but ultimately chooses Hideyuki and Satoru.
*Shiro tells Takeshi where Satoru and Hideyuki are and tells him to kill them. Takeshi later finds out that they aren't there, until he confronts Shinji, Ren and Shuichi at the same time.
*Reiko questions Shuichi about the thing that attacked her last time.
*Ren is enraged by Shinji's decision to include Mitsuru as his comrade.
*Hideyuki brings Satoru to lunch with his family to teach him the moral lesson about being a hero.
*Satoru kills Hideyuki and shatters the Alternative Deck.
==Plot==
to be added
==Cast==
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===Guest Cast===
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==Advent Cards==
*Cards used:
**Ryuki:
***Sword Vent
**Tiger:
***Final Vent
**Imperer:
***Spin Vent, Gigazelle
**Alternative Zero:
***Psyco-Rogue
*Weapons/Powers summoned:
**Ryuki:
***Dragsaber
**Tiger:
***Crystal Break
**Imperer:
***Gigazelle Stab, Gigazelle
**Alternative Zero:
***Psyco-Rogue
*Advent Card appeared before episode's preview:
**Strike Vent (Tiger)
==Errors==
to be added
==Notes==
*This episode aired alongside Ninpu Sentai Hurricaneger episode 40, Scroll 40: Decoy and Ninja Law.
*Viewership: 8.7%
*When Shuichi confronts Asakura in the vacant Room 401, he told Asakura that he will be his "main dish".
**This catchphrase would be used eleven years later in Kamen Rider Wizard, with Kousuke Nitoh using Shuichi's words as his main catchphrase every time he performs his finisher.
*This is the only episode Alternative's contract card is used.
*This is the final appearance of Hideyuki Kagawa.
**With Kagawa's death, this marks the end of the Alternative Riders, leaving Tojo as the last surviving member of Kagawa's Research Lab.
*Up until this episode, the number of victims that died inside the Mirror World are four people so far. Miyuki Tezuka does not count, since he was outside of the Mirror World thanks to Shinji, but dies later after being struck by Ouja's Veno Crash.
==Digital Releases==
*Kamen Rider Ryuki DVD Volume 11 features episodes 41-45.
*Kamen Rider Ryuki Blu-ray Volume 3 features episodes 35-50.http://www.toei-video.co.jp/special/ryuki
Ryuki DVD Vol 11.jpg|Kamen Rider Ryuki DVD Volume 11
813ElyAvpTL SL1460 .jpg|Kamen Rider Ryuki Blu-ray Volume 3
==References==
Category:Rider Death Episode