(From picture 1 to 3) Daniel Wu, Gao Yuanyuan and Louis Koo are seen in the romantic comedy "Single Men and Women". [Photo: yule.sohu.com]

Hong Kong director Johnnie To is working to complete his "men-women" romance-themed trilogy with a new film starring Louis Koo, Daniel Wu and Gao Yuanyuan, Sohu.com reports.

The romantic comedy under the working title of "Single Men and Women" ("Dan Shen Nan Nv") is about a love triangle in an office setting.

Gao Yuanyuan plays an unhappy investment analyst who must choose between her playboy boss (Louis Koo) and an alcoholic architect (Daniel Wu).

The film is slated for release in March.

Johnnie To is working on the film with his frequent co-director and writer Wai Ka-Fai, known for directing the 1995 action film "Peace Hotel" starring Chow Yun-Fat.

To and Wai's successful cooperation is also marked by the previous films in the "men-women" trilogy, namely "Love on a Diet" ("Shou Shen Nan Nv"; 2001) and "Needing You..." ("Gu Nan Gua Nv"; 2000), both starring Andy Lau and Sammi Cheng.

Besides romance, crime and action dominate the subjects of To's other notable films. Among them, "Vengeance" ("Fu Chou"; 2009) and "Sparrow" ("Wen Que"; 2008) have been shown in competition at the Cannes and Berlin film festivals, respectively.