A young couple are enjoying a romantic rendezvous in a hidden grove at a city park at twilight. It turns out to be an illicit affair. The woman is the married wife of a law professor and her lover is one of his students. Their privacy is interrupted by the arrival of a speeding taxi that crashes into an embankment nearby. Inside the driver is seen struggling with the backseat occupant. It ends badly with the driver murdered and his body dragged into the bushes. The killer flees and the young couple are faced with a dilemma. Should they go to the police and risk exposing their affair or remain silent? This is the pressing issue that drives the narrative of The Assignation (Japanese title: Mikkai, 1959), directed by Ko Nakahira.