Gyeong-ah works as a caregiver and lives alone. The only one she can rely on is her daughter, Yeon-su, but it's hard to see her after she moved out on her own. Meanwhile, Yeon-su, who is suffering from her ex-boyfriend, Sang-hyun, argues with him again and visits her mother’s house. After Yeon-su left, Gyeong-ah receives a shocking message from a stranger.
2007年躁動不安的暑假,熱愛游泳的13歲女孩隨母親搬到鄉下外婆家,在游泳館邂逅了小她一歲、擁有過人天賦的謎漾男孩。女孩活躍直率,男孩內斂溫吞,男孩在一場海邊的溺水意外救了女孩,也就此寫下兩人的難解緣分。她追著他打鬧嬉戲,他和她分享專屬秘密,直到高中升學之際,少年為了追逐游泳夢離開小鎮,因此失聯。2014年他們重逢之際,一個迷失於游泳訓練,一個深困於自卑心結,相望相知的彼此,能否再續前緣?
影片改编自楡周平的同名小说,新冠疫情背景,讲述因疫情被迫远程工作的晋作,决定从城市搬到可以享受垂钓的三陆,寻找新生活方式。但也渐渐发现,当地存在的“空房”等问题。