2016年夏，在法国长大的华裔，美食评论家，美食杂志资深编辑林静芸，来上海探访美食和展开寻根之旅。此时，林家老宅已经被改造为一栋餐厅，餐厅中挂满了珍贵的旧上海报纸和旧物，记载了当年的故事。林静芸无意间找出一本日记，打开翻看，里面讲述了一个叫天婴的女孩跌宕起伏的爱情传奇。20年代末的大上海，洪家的帮派、林家的财阀、许家的警局三足鼎立，雄踞上海滩，平静之中，暗流涌动。
　　隆福戏院，天婴女扮男妆代师傅九岁红登台救场，却不想一炮而红，成了名角儿，也让洪帮二当家罗浮生和许家公子许星程一见倾心，各施所长展开追求。
　　天婴情窦初开，以为儒雅温柔的许星程会是甜蜜的初恋，却造化弄人，偏偏总和痞气霸道的罗浮生不期而遇，纠缠不清。不知不觉间，天婴内心的情感天平也在悄悄发生变化。
　　与此同时，段天赐视天婴为未婚妻，以保护为名囚禁她，却被她冲破恩情绑架，与之划清界限；洪家千金洪澜暗恋罗浮生，处处刁难她，却被她以真性情打动，情敌变闺蜜。

In the summer of 2016, Chinese-born food critic and senior editor of food magazine Lin Jingyun, who grew up in France, came to Shanghai to visit food and to find her roots. At this time, the old Lin House has been transformed into a restaurant, the restaurant hung with valuable old Shanghai newspapers and Old Things, recorded the story of the year. Lin Jingyun inadvertently find a diary, open read, which tells a girl called days baby ups and downs of love legend. In the late 1920s, Hung Ga's gang, the Lin family's plutocrats and the Xu family's police station dominated The Bund. Longfu Theatre, the day baby girl disguised as a nine-year-old master Hong came on stage to save the scene, but did not want to be a hit, became a famous actor, also let Hong Gang's second master Luo Fusheng and Xu Xingcheng, the son of the Xu family, fell in love with each other at first sight, each with their own strengths to pursue. Tian Ying had just begun to fall in love. She thought that the elegant and gentle Xu Xingcheng would be her sweet first love. However, fate made a fool of her. Unfortunately, she always ran into the domineering and domineering Luo Fu unexpectedly and got entangled with him. Imperceptibly, the day baby's inner emotional balance is also quietly changing. At the same time, Duan Tianci regards Tian Ying as his fiancee and jails her in the name of protecting her, but she breaks through her kindness and kidnaps him to draw a line between him and her. Hong Lan, the daughter of the Hong family, has a crush on Luo Fusheng and tries to make things difficult for her, but is moved by her true nature, a rival in love turns into a bestie.