To support her father's medical fee and the living expenses of her family, Man rejects an arranged marriage and moves to Beijing from Sichuan. She received little education and does not have Beijing's household registration. So, she becomes an elevator girl with a meager salary and works in a sunless environment. Her friend suggests her becoming a surrogate mother, will she take this offer?文為了籌措父親的醫藥費及全家的生活費,拒絕母親的包辦婚姻,毅然離鄉別井,從四川來到北京。她學歷低,又沒有當地戶籍,只能當電梯女郎,終日面對遮蔽的空間,開始其「不見天日」的生活。電梯女郎的薪酬微薄,文只好另謀出路。她的朋友娜娜介紹她去當代母,究竟文會否出賣其子宮以換取「光明」的日子呢?