S01E860: The Security System's Pitfall

Kogoro is hired to catch a thief. While working the case, the body of Junko's neighbor Kitagami is discovered in the parking lot behind her apartment building. Kogoro reasons Kitagami got drunk and accidentally fell from his room, number 704. Conan finds it strange that Kitagami left his front door unlocked when his apartment was fully equipped with anti-theft devices...