One thing is made abundantly clear in Alan Mak and Felix Chong’s new film, Overheard – being a cop sucks. Sure you get to carry a gun but you work long hours in a high stress environment within an almost militaristic chain of command. Living your job and sacrificing relationships for a lousy salary in the hope of chasing down scumbags living the good life can be demoralising for even the most optimistic of coppers and takes all the fun out of crime fighting.

It’s hardly surprising that, when the opportunity comes along for surveillance operatives Johnnie (Lau Ching Wan), Max (Daniel Wu) and Gene (Louis Koo) to make a few bucks on the stock market, they only momentarily balk at the fact that their information was gleaned from eavesdropping the insider traders they are out to bust. Max has an over-protective father-in-law to appease, Gene has a wife and three kids, one with leukaemia, to support and while Johnnie may live on his own, he’s been banging his partner’s wife (Zhang Jingchu) for some time now and is thinking seriously about making a commitment. All of this costs our three protagonists far more than their paltry cop’s paycheques can stretch to.

Overheard opens well as the trio set about their target, E&T’s offices, installing bugs and hidden cameras. It is taut and suspenseful and promises much for the rest of the movie. And at times the film does delive. It is occasionally tense, exciting and even funny, proving that the directors have the talent and know-how for this kind of film - but the story never really gets out of first gear.

The setup is good and the characters are interesting. Admittedly Daniel Wu pretty much evaporates in the second half, but Louis Koo has a meaty if typically melodramatic role, and we see the welcome return of Michael Wong, camping it up as the villainous CEO of E&T. That said, the characters don’t get much time to pause and consider the ramifications of their actions, nor does the film pull any surprises along the way. Quite simply, the crime committed is not nearly daring, dastardly or interesting enough to demand such lofty dramatic pretensions, while the ramifications are predictable and underwhelming. Blame has to lie with Mak and Chong for going ahead with what is clearly an under-developed screenplay. There were so many interesting directions the writer/director pair could have taken this tale, but instead play it straight down the line, as quickly, economically and unadventurously as possible.

Some blame Andrew Lau’s departure from this creative team for the end of the good times, but the rot set in when he was very much still on board. Derek Yee is involved this time out, but even he can’t help matters, save for securing a heavyweight A-list cast who should be demanding better material. After Infernal Affairs III, Confession of Pain, Lady Cop & Papa Crook and now this, one has to start asking whether Alan Mak and Felix Chong were ever really all that good to begin with. Or were the first two Infernal Affairs films just happy accidents rather than the jubilant salutation of a new creative force in Hong Kong cinema that we all had hoped they were? James Marsh