- Tittle: 迷云二十天 / Mi Yun Er Shi Tian
- English title: The Undisclosed
- Genre: Thriller, suspense
- Episodes: 20
- Broadcast network: MediaCorp Channel 8
- Broadcast period: 2006-April-03 to 2006-April-28
- Air time: Weekdays 21:00-22:00
Carol, who works in Hong Kong, returns to Singapore for her wedding dinner after her engagement to Hongkong resident Superintendent Cheng Musheng. After meeting with a longtime friend Rachel, she disappears.
Yan Kexin, a detective and former classmate of Carol's, volunteers for the case and devotes herself to locating Carol. Musheng also embarks on a relentless search for his fiancee with the Rachel's help. Kexin discovers that Carol's stepmother and her son may have been plotting against Carol, while Musheng learns that a secret society is also searching for Carol.
Then, someone claims to have seen Carol. Does this mean that Carol is still alive? Did she concoct her own disappearance and why? How did she get involved with the secret society? As Kexin and Musheng unravel the mysteries revolving Carol, what will they find?
- Li Nan Xing as Cheng Mu Sheng
- Pat Huang as Yan Ke Xin
- Constance Song as Rachel
- Ong Ai Leng as Carol
- Andrew Seow as Zeng Tian Ci
- Song Li Hua as Zeng Bi Xing
- Rayson Tan as Chong
- Brandon Wong Raymond
- Huang Shi Nan as Ivan
- Zhu Hou Ren as Long Tou
- Weng Xing Au as Steven
- Best Actor, Star Awards 2006 - Li Nan Xing
- 9th Highest Viewership Drama among MediaCorp 2006 series, Star Awards 2006