Mara Voss, a young woman with a secret habit of stealing objects she feels are "meant" for her, becomes obsessed with an antique black mirror owned by the mysterious widow Agnes Vale. After stealing the mirror, Mara discovers that it seems to reveal hidden events and secrets but never clearly enough to know what they truly mean.

As Mara follows its visions, she begins doubting her fiancé, her memories, and eventually herself. She uncovers evidence that she may have encountered the mirror years before and forgotten it entirely. The deeper she searches for the truth, the more dangerous her obsession becomes.

In the end, Mara must face a disturbing question: Is the mirror truly supernatural, or is the real danger the human need to believe that suspicion is truth?