The Constable: Lam Kwok Kuen, nearing retirement and raising a mentally challenged son by himself, is a police officer whose sole requirement on the job is oversee the department fleet. Despite this, he remains active in the front line of police service, putting his life on the line for the sake of others, his heroism bettering even the most seasoned professionals. He fights the bad guys, putting criminals behind bars, upholding the law at any cost, for as his adage proclaims, to live a day surmounts to pursuing justice relentlessly, whether life or death proceeds in its aftermath.