Serenade of Peaceful Joy

Serenade of Peaceful Joy, or previously known as Held in the Lonely Castle, is a 2020 Chinese period drama series loosely based on Milan Lady's novel of the same name. It is directed by Zhang Kaizhou, and stars Wang Kai as Emperor Renzong of Song and Jiang Shuying as Empress Cao. The series aired on Hunan TV starting April 7, 2020.

Synopsis
When Zhao Zhen discovers his biological mother is not the Empress Dowager Liu E, but her maid Li Lanhui, he arranges a marriage between his beloved daughter Princess Fukang and the Li family's son Li Wei as compensation for his lack of filial piety. In the political arena, Zhao Zhen strives to maintain a balance of power between the conservative and progressive factions after the Qingli reforms experiences a significant backlash from the former.

Inside the palace, Emperor Renzong faces the dutiful Empress Cao, the troublesome Zhang Mihan, and the gentle Lady Miao. As time passes, all of his sons don't survive past childhood and he is left without a male heir.

Outside the palace, Huirou's married life with Li Wei is far from pleasant – displeased with her foolish and boring husband, and annoyed by her prying in-laws, Huirou develops an even closer relationship with her eunuch Liang Huaiji. After a serious dispute with her husband's family, Huirou knowingly breaks the law by charging back to the palace the same night with the help of Huaiji.

The next day, conservative official Sima Guang presents a scathing memorial to Zhao Zhen, heavily criticising Huirou for her selfishness and violation of imperial etiquette. Zhao Zhen had always encouraged freedom of speech and supported a supervisory system that would maintain disciplinary surveillance over bureaucrats and royalty, and must ultimately choose between his daughter's happiness and the stability of government.

Main

 * Wang Kai as Emperor Renzong
 * Personal name Zhao Zhen. A benevolent and merciful emperor who would bring about one of the most economically and culturally prosperous eras of the Song dynasty. However, he encounters much backlash from conservative officials while trying to implement the progressive Qingli Reforms.
 * Jiang Shuying as Empress Cao
 * Personal name Cao Dansu. An empress who abides by her duties but is distrusted by the Emperor due to the power her relatives wield in court and because she reminds him of the Empress Dowager.

Imperial Family

 * Ren Min as Princess Fukang
 * Personal name Zhao Huirou. Zhao Zhen's beloved daughter. She is unable to deal with the suffocating atmosphere in the Princess' Mansion, where her husband resides as well, and develops romantic affection towards her eunuch Liang Huaiji. Refusing to swallow the insults from her in-laws, she charges back to the imperial palace one night with Liang Huaiji's help, and her rebellious actions lead to an uproar in court.
 * Wu Yue as Empress Dowager Liu
 * Personal name Liu E. The regent of the empire for twelve years and the Emperor's adoptive mother. She sincerely loves him but is aware that their relationship is cold and cordial.
 * Wang Churan as Noble Consort Zhang
 * Personal name Zhang Bihan. One of the best dancers in the palace. She met Zhao Zhen as a child and fell in love with him ever since — even though the Emperor has forgotten. She can't adjust to life in the inner palace and grows paranoid, convinced that everyone is against her. All of her daughters pass away at a young age, and her mental health is affected greatly.
 * Xu Lingyue as Noble Consort Miao
 * Personal name Miao Xinhe, nickname Wo'er. The mother of Zhao Huirou and Zhao Zuigxinglai, and Zhao Zhen's childhood sweetheart. She only cares about her children's well-being while also developing a rivalry with Zhang Bihan. She's a close friend of the Empress.
 * Lu Yanqi as Lady Xu
 * Personal name Xu Lantiao. Originally a maid, she's responsible for indirectly causing the death of Zhang Bihan's eldest daughter. She holds a grudge against Nanny Gu because of her favoritism towards Zhang Bihan. However, she ends up reconciling with Nanny Gu who later kill her while pregnant with the Emperor's child.
 * Liu Zihe as Lady Yu
 * Miao Xinhe's friend who despises Zhang Bihan.
 * Wang Yuchao as Emperor Yingzong
 * Personal name Zhao Zongshi. Adopted son of the Empress and a member of the imperial clan. He was Zhao Huirou's childhood companion and friend.
 * Yang Yue as Empress Guo
 * An outspoken and fierce woman, she was chosen by the Empress Dowager to become the empress. She sincerely loves the Emperor but her hot-headed personality leads to her deposition. She mysteriously dies shortly after returning to the Emperor's good grace.
 * Xiao Yifen as Ninth Princess
 * Qian Jin as Tenth Princess
 * Zhao Da as Prince of Zhou
 * Lu Xing as Li Wei
 * Princess Fukang's husband.

Imperial Court

 * Yang Le as Han Qi
 * Chancellor of the empire for a decade and one of the officials responsible for the Qingli Reforms.
 * Yu Entai as Yan Shu
 * Renowned poet and calligrapher.
 * Liu Jun as Fan Zhongyan
 * An official who advocated for sweeping reforms to the court and political system, and proposed the changes that kickstarted the Qingli Reforms along with Han Qi and Fu Bi.
 * Li Yanan as Fu Bi
 * Close colleague of Fan Zhongyan and Han Qi.
 * Zhang Benyu as Ouyang Xiu
 * Feng Hui as Xia Song
 * Tan Xihe as Lu Yijian
 * Chen Weidong as Wen Yanbo
 * Chu Junchen as Sima Guang
 * Ji Chen as Di Qing
 * Ding Jiawen as Cao Ping
 * He Jianze as Bao Zheng
 * Yang Shuo as Shi Jie
 * He Minghan as Wang Gongchen
 * Zhao Haoyuan as Su Shunqi
 * Yu Peishan as Cao Yi

Servants

 * Bian Cheng as Liang Huaiji
 * An eunuch who has served Princess Fukang since a young age, and develops romantic affection for the Princess.
 * Ye Zuxin as Zhang Maoze
 * Head eunuch. The Emperor and Empress' close aide. He has an unrequited love for the Empress, but is willing to bury his feelings and simply be a confidante.
 * Cao Xiwen as Nanny Gu
 * Zhang Bihan's mother figure who helps her to get out of trouble. Due to her influence on her, she also contributes to Zhang Bihan's paranoia that sets her against the Empress and Miao Xinhe, as she is convinced that they are responsible for the death of Zhang Bihan's daughter. She later murders Dong Lantiao after realizing that Zhang Bihan had discovered the truth and kills herself to save her.
 * Chu Feng as Ren Shouzhong
 * Hu Shuangquan as Liang Quanyi
 * Liu Xizi as Zhang Chengzhao
 * Zhang Xiaoyue as Xiu Niang
 * Wang Xiao as Gu Sanxi

Others

 * Zhang Tian'ai as Chen Xichun
 * The Emperor's first love, who was sent away due to being unfit to be empress.
 * Guo Hong as Lady Yang
 * Li Jiaxin as Fu Ruolan
 * Fu Bi's daughter.
 * Wu Xiaoyu as Xue Yuhu
 * Jin Yiying as Jia Qingzi
 * Tian Luhan as Huan'er
 * Bu Yaping as Cao Ping's wife
 * He Yuxiao as Prince of Yan's grandson
 * Feng Youran as Bitao
 * Ma Yixun as Yan Jidao
 * Hu Haobo as Liang Yuansheng
 * Li Peize as Man Jidao
 * Hou Mingyao as Xia He

Production
Principal photography commenced on 5 January 2019 at Hengdian World Studios.

Casting
On 8 November 2018, Wang Kai was announced as the male lead, and the director confirmed that the focus of the drama would be on the emperor's reign, while still keeping the original romance between Princess Huirou and Liang Huaiji intact. On 7 December 2018, the rest of the cast was announced. In May 2019, the drama wrapped up filming and announced guest appearances by several actors.

Original soundtrack
The Original Soundtrack album (清平乐 电视剧原声带) was released on April 30, 2020, and was produced by Meng Ke and Lu Liang. The compilation album of the drama ending themes (清平乐 电视剧片尾曲合辑) was released on May 1, 2020, and was produced by Dong Yingda.

Ratings

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