Kim Seong-geun (Jae-yeong Jeong), despondent over being dumped by his girl, decides to end it all by jumping into the Han River, but instead wakes up on a tiny island in the middle of the waterway, now a castaway in the teeming heart of civilization. Part social commentary, part romantic adventure with hints of science fiction, Lee Hey-jun's film touches on topics ranging from economic disparity to the alienating nature of modern urban existence.