When Love Walked In
Promotional poster
Also known as	The Prince Who Lost His Castle
Genre	Romance comedy
Directed by	Chen Zhi Han Feng
Starring	Victoria Song Calvin Chen Zhou Mi
Opening theme	When Love Walked In by By2
Ending theme	Pass By by Jeanie Zhang
Countries of origin	China Taiwan
Original language	Mandarin
No. of episodes	32
Production
Producer	Meng Xue
Production locations	Shanghai, Hainan, Taipei
Production company	Shanghai Film Co.
Original release
Network	GTV
Release	27 August (2012-08-27) – 2 November 2012 (2012-11-02)

When Love Walked In (Chinese: 爱情闯进门; pinyin: ài qíng chuǎng jìn mén) is a 2012 Chinese-Taiwanese co-produced television series starring Victoria Song of f(x), Calvin Chen of Fahrenheit and Zhou Mi of Super Junior-M.^[1] The series premiered on GTV on 27 August 2012.

Victoria Song won the Best New Actress award at the China TV Drama Awards.

Young, talented, and handsome Qin Yujiang (Calvin Chen) receives orders to look for Chairman Yuan's long lost granddaughter, Shen Yayin (Victoria Song). As grandfather tried every means to separate her and her father, Ya Yin often moved houses and hid away from her grandfather since she was young. When her father died, Ya Yin dislikes her grandfather as she feels that he has ruined her childhood happiness and was part of the cause contributing to her father's death. Ya Yin's guardian plotted a plan for her own daughter, Yu Ru (Ya Yin's cousin) to impersonate as Ya Yin to dupe Chairman Yuan into thinking that she is actually his long-lost granddaughter. Yu Jiang gradually enters Ya Yin's heart but refuses to admit his love for her because she's Chairman Yuan's granddaughter. Ya Yin's evil cousin also became an obstacle between Ya Yin and Yu Jiang's love.^{[citation needed]}

• Victoria Song as Shen Yayin
  • Xu Yuhan as young Ya Yin
• Calvin Chen as Qin Yujiang
  • Bian Cheng as young Yu Jiang
• Zhou Mi as Li Shanglin
• Sean Lee as Gu Qingfeng
• Tong Xiaoyan as Chen Yuru
• Emily Cao as Xiao Fen

• When Love Walked In on Weibo (in Chinese)