The story follows a recent divorcee who spends her daily commute fantasizing about a seemingly perfect couple who live in a house that her train passes daily, but something shocking happens there one day.
The morning Stella decides to take her own life, a stranger knocks at her door claiming the guest room he booked for the night. Surprised but charmed by this man who seems to know her very well, Stella decides to let him in. But when Sandro, the man who broke Stella's heart, joins them at home, this odd situation turns immediately into chaos.