The short mini-series format is fantastic for mystery and intrigue. I have been meaning to explore this promising genre for while. I chose Day and Night due to its strong international reception. Although it delivered in terms of an intriguing plot and decent script, the overall execution was poor. It starts out as a mystery/suspense but ends up like just another cop drama.

The plot is built around former lead investigator Guan Hongfeng's secret mission to clear his fugitive twin brother Guan Hongyu, who was wrongly accused of brutally murdering an entire family. Hongfeng conceals Hongyu, who covers for him at night while he wrestles with his fear of the dark. That they are identical twins gives wide scope for multiple fun plot twists, something the writers took advantage of. Back at the crime investigation department, the twins alternate as Hongfeng to secretly try to solve Hongyu's case while assisting with ongoing investigations. There is only one conspiracy to uncover; all the other cases are presented as police procedurals so we only have to keep track of one set of clues for the one big whodunit. There were too many side cases - the drama ended up morphing into an action oriented police thriller with great high speed chases and fist slugging action. The one good, meaty suspenseful, whodunit conspiracy I was so looking forward to ended up taking a back seat. The many other excellent cop thrillers out there sets a high bar, relative to which this is at best a mediocre effort.

Where this drama crashed was with the uninspired acting by a B-list cast. The lead actor (Pan Yue Ming) only did a decent job playing twins - this is hard to do but it can be a fun, challenging role for a more versatile actor to shine in. He was good at conveying a barely discernible difference in mannerisms between each twin. But while his Hongyu was engaging as the more outgoing and charismatic twin, his portrayal of the introverted, cerebral Hongfeng fell far short. This character should have more intensity and quiet gravitas; an intellectually intimidating veteran detective with a giant secret instead of a lethargic, sleep deprived, monotonic and mostly expressionless character. Zhouxun (Wang Long Zheng), Hongfeng's ex-partner and successor as head of the department was well acted. He came across as a politically savvy, mercurial, cunning and suspicious friendemy of Hongfeng but tended to over-act, notably the temper tantrums. The critical casting error was Liang Yuan as Zhou Shutong, Hongfeng's rookie newbie mentee. This actress thinks rookie is synonymous with vacuous and that best describers both her performance and her favorite facial expression. This destroyed the chemistry of the entire cast - they couldn't interact with her nauseating deer in the headlights Bambi routine. Consequently, there was no convincing team dynamic between the cast. This rapport did eventually emerge and feel natural in the last 10 episodes, notably in scenes with no Shutong. Unfortunately Shutong got a lot of airtime as her role closely touched all of the lead characters. They should have just cut their losses by turning her into the victim of a serial killer.

The final episode was excellent, ending the show on a high note although only part of the conspiracy is revealed. There is no hard air date for the sequel and few details. Given the mediocre execution, I would not be surprised if it never eventuates. I am only mildly curious to find out what really happened so I won't be crying if it never happens. Overall this is an ok watch, it didn't live up to the hype for me although I will watch a few more in this genre.