One and Only (Chinese: 周生如故) is a 2021 Chinese period romantic television series, starring Ren Jialun and Bai Lu.

[1] The series is based on the novel Yi Sheng Yi Shi Mei Ren Gu (一生一世美人骨) by Mo Bao Fei Bao.

[2] The series is followed by a modern companion series Forever and Ever.

Both series were adapted from the same novel, released back to back, and follows the same characters in different eras (one historical, one modern).

The series began filming in November 2020,[3] and wrapped up in January 2021.