My Perfect Stranger

All This Is a Coincidence? (1x4)

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With the day drawing closer, Hae-jun experiences mounting anxiety over the possibility of failing to prevent the murder, given his limited information and unexpected developments. While the school is on a field trip, a new student teacher is introduced, whom Yoon-young finds strangely familiar. Later that night, while alone at home, Yoon-young recalls the true identity of the student teacher.