一个十八岁的少女阿雪，因家境贫困，被卖予刘姓老头为妻。刘老头个性变态，阿雪每天白天做家务，晚上还得承受刘老头的种种性虐待。某日，阿雪偶偶逃犯华仔，两人一见钟情，开始交往……
新婚的美麗女孩隨著丈夫工作地調動搬到了東京，在高房價的東京卻幸運地用低廉的房租找到了一間古老的大宅，付出的代價是這古老的大宅院隱藏著獸性的房東，當丈夫離家上班時，邪惡的房東就藉故進入房屋內檢查，陷害美麗的女子偷竊的大宅院裡面的高價的古董，並且以鋒利的武士刀架在女孩的脖子上，逼迫美麗純真無助的女子，用完美無暇的肉體賠償這一切誣陷的損失，古老大宅院和獸性房東成為女孩的人間煉獄..
This long-lost masterpiece of hardcore gay erotic cinema centers on a handsome young stud who rides his motorcycle through myriad sexual encounters, from a soccer game’s locker room to a phantasmagoric and deeply melancholy orgy. A labyrinth of all-male fantasies whose outstanding beauties always end up fading away while leaving their sensual protagonist dealing with his own loneliness, EQUATION was directed with supreme grace by the mysterious Dietrich de Velsa (aka Francis Savel/Frantz Salieri). A former painter, de Velsa was also the owner and artistic director of La Grande Eugène, one of the first drag cabarets in Paris. Years later, he collaborated with Joseph Losey on MR. KLEIN (1976) and DON GIOVANNI (1979). His one and only film, EQUATION TO AN UNKNOWN stands as one of the most extraordinary erotic films of all time. “The most melancholic porn film I’ve ever seen. It’s very sad, and aesthetically beautiful. Just a young man wandering through several depictions of love and choreographies of love-making it’s like a ceremony, a ceremony of fantasies, especially the last sequence where the main character recalls all his previous fantasies, which come one by one around his bed and make love to him. I think it’s one of the most beautiful film sequences of French cinema.” –Yann Gonzalez
負けず嫌いの性格ゆえに、どんなことも簡単に割り切ることができない美咲（瀬戸早妃）。外食産業の商社で働いている彼女は、結婚する先輩・倫子 （矢吹春奈）から式の発起人になってほしいと頼まれる。それを受けた美咲だったが、無理難題を要求してくる上司を筆頭に周囲の人間に翻弄（ほんろう）されることに。ある時、一人の男性が美咲の前に現れ……。
