Mei has amnesia following a serious accident but is living a fulfilling life, enjoying her work and surrounded by her wonderful fiancé and best friend. One day, she falls under the suspicion of a murder of which she has no memory, and her comfortable life falls apart.
Who is an ally, and who is an enemy? Mei is betrayed by those she trusts as she draws closer to the truth, but she does not actually know herself and is carrying her own secret.
