本片根据诺贝尔文学奖获得者海明威的《过河入林》一书改编。《过河入林》是海明威于1949年去意大利旅行和打猎回国之后所写的一部长篇小说，主人公坎特威尔上校身上有作者本人的影子。坎特威尔上校随着年龄的增长，心情日趋颓唐，到威尼斯去打野鸭作消遣，并到意大利北部凭吊过去的战场。他回忆过去的爱情，考虑到死亡的问题，感到孤独绝望。

　　The nightmare was about a demonic possession. A long time ago, there was an evil in a small town and it was jealous of the girl and would never let her go, since the devil loved the girl. One night, the evil raped the girl and she became pregnant. After months the girl could not hide her baby, her father figured her secret out and clapped the girl in irons and locked her room door. But the evil put the gun to her father' temple and saved the girl. The father had a stroke and had been sleeping on the bed for three months and died. Time went on and the girl brought a child into the world. Naturally, people who were living in the village heard the story and they did not want to see neither the girl nor the baby since when the baby was born, plants dried in the field, fishes lost in the lake and people had prayed to the god for rain, but nothing changed in the village. People got so angry, dug a hole in front of the fountain, put her into the hole and threw stones at her face. The girl died soon after. The evil went off the deep end, took a revenge of the village and killed everyone except two sisters because the evil wanted them to take care of its baby...

　　身為劇場女演員的珊曼莎，下戲後與友人費莉西雅合夥經營「打包狗」寵物服務店，在迷人的帥醫師赫曼的委託下，珊曼莎照顧起一隻名為亨福瑞的高貴馬爾濟斯，這看似平凡又單純的委任之務，背後竟牽涉一連串的謊言與神秘組織的操控。從那刻起，珊曼莎的日子不再安寧，出門試鏡被一群像吸血鬼的屁孩跟蹤包圍，深夜家門更遭到陌生男子破門而入，為了既得利益，亨福瑞成為眾人角逐之物。珊曼莎能相信眼前的那位充滿魅力的男人嗎？究竟她的愛能像動物那樣純粹、忠誠且毫無保留嗎…

《一女一男》是一个现代故事，讲述的是年轻人在当今社会复杂的人际关系、联系和亲密关系中穿梭的故事。 　　这部电影讲述了一个女孩的故事，一个男孩的故事，以及一个女孩和一个男孩的故事。