Kagi no Kakatta Heya (鍵のかかった部屋, Locked Room) is a 2012 Japanese Getsuku television drama series distributed by Universal Pictures under the locked-room mystery genre broadcast by Fuji Television from April 16 to June 25, 2012.

It is based on the Kei Enomoto novel series by Yusuke Kishi titled The Glass Hammer (硝子のハンマー), The House of Will-o'-the-Wisp (狐火の家), and The Locked Room Murders (鍵のかかった部屋).

The drama stars Satoshi Ohno, Erika Toda, and Koichi Sato, and received a viewership rating of 16.0% on average.

Enomoto is not an easy person to familiarise oneself with, always calm, quiet, and unapproachable, with a past that is unknown to others.

Aoto is pure and acts upon her instincts, whereas Serizawa is a prideful elitist who sees time as money and will not take on any job that is not profitable.