Auspicious red is the colour of Chinese New Year, but this festive offering wants you to turn green - with environmental awareness.

What is the point of making more money if you cannot take a breath of clean air or drink a drop of clean water?

The stark message here is that before humans destroy Earth with wanton development and endless appetites, they should stop and think about the consequences.

Wait a minute, is this a movie from the Hong Kong funnyman who gave viewers entertaining laugh riots such as Kung Fu Hustle (2004) and Shaolin Soccer (2001)?

Not to worry, despite the save- the-earth memo, this is very much a Stephen Chow-directed work and that means ludicrous situations and nonsensical jokes.

Some of the best bits involve Taiwanese singer-actor Show Lo gamely dressed up as a dreadlocked octopus who gets his tentacles manhandled, Liu Xuan trying desperately to convey the idea of a mermaid to two disbelieving, pedantic cops and Shan getting repeatedly thwarted as she tries to attack Liu.

There are also throwaway jokes, such as when a command to "gun kai" (get lost) is obeyed by underlings literally rolling ("gun") away ("kai").

What does not quite work is a bland Kitty Zhang (previously seen in Chow's CJ7, 2008) as a vampish businesswoman who wants to get into bed with Liu on Green Gulf.

And despite China star Deng's (The Four, 2012) best efforts at big expressions, one cannot help but wonder if the film would have been funnier if Chow, who can be both exaggerated and supremely deadpan, had acted instead.

But he would probably have been criticised for lining up a romance with the 19-year-old Lin had he done so - not the kind of splash he would want Mermaid to make.