Donggam plot
At the university where she studies, So-eun accidentally stumbles upon a radio, which she then takes home. That evening, during a lunar eclipse, the radio starts making noise; one In makes a call. So-eun decides to respond, and she starts talking to him. In turns out to be studying at the same university, so they jokingly decide to meet the next day near the university entrance. After not seeing each other at the agreed place and time, they both seek radio contact to find out. They make the shocking discovery that they don't live in the same era.