Write a 1000-word mystery narrative told entirely from the first-person perspective of an antique mirror. The story must use a non-linear timeline, jumping between the present day and three distinct past decades (1920s, 1960s, 1990s) based on reflections the mirror 'witnesses'. The climax must reveal a crime that connects all three eras, without ever leaving the room the mirror is currently in. Do not use dialogue tags; rely on context and tone to identify speakers.