In Promontory Condo, Hong Kong, a veteran sergeant named Tai tumbles from a high floor and supports serious wounds. He frantically attempts getting up, yet winds up breaking one of his legs. After some time, the police show up on the scene and track down Tai canvassed in blood. They likewise find Ling, a senior examiner, oblivious on the seventh floor’s hall. A few cops are then dispatched to track down the culprit, yet all to no end.
Afterward, in the emergency clinic, the cops of groups An and B contend with one another as the head of group B; George, denounces Reviewer Ling of being liable for Tai’s ruthless condition. Sooner or later, Ling recaptures awareness and ends up in the clinic with his significant other; Hazel and their embraced child; Sonny. As the family is having a close to home second, Ling’s associate; Phantom, hinders them, also, gets some information about the homicide.
Be that as it may, the last option appears to have lost his new recollections in light of the serious effect on his head. That evening, Ling and Phantom visit Tai, who is lying oblivious in the ICU. As Ling watches in dismay, Apparition makes a difference him review the episodes from the past days. He makes reference to that the whole police division has been isolated into a few gatherings to settle the new homicide cases, however up until this point, there has been no leap forward.
The blood draining chronic executioner has previously killed 2 honest residents in the previous month, yet, his rationale is obscure. His killing strategies are similarly frightful. The executioner drills openings into his casualties’ bodies, depletes their blood out, and passes on them to kick the bucket. Besides, Apparition uncovers that Tai and Ling were seen entering the Promontory Loft at 3 p.m. the other day. As indicated by the CCTV film, Tai was 15 minutes sooner than Ling.
Notwithstanding, the police can’t decide why the two went to Promontory Loft with practically no reinforcement. The following day, Ling heads to his work environment, the police central command, furthermore, illuminates his manager that he will proceed to deal with the homicide case. The manager recommends that he rest and let George’s group handle the case yet Ling is determined on tracking down the executioner.
Afterward, Apparition approaches Ling in his lodge, what’s more, begins talking about the case. He uncovers that the principal casualty was a games teacher named Ken Cheung, who was a fair man with no lawbreaker records. The subsequent casualty was a 40-year-old comic craftsman named Juno Mama, who had no spouse, cash or adversaries. As indicated by Apparition, the association between the casualties is the way they kicked the bucket, as both were blood-let utilizing an electric drill.
Also, the two killings happened close Rugged Island, a similar spot where Ling lives. The following day, Ling and Apparition visit Landmass Condo and begin looking for certain hints. Out of nowhere, Ling begins getting pieces of his recollections back, what’s more, reviews that he was on the ninth floor, not the seventh, when he saw Tai lying on the ground. In the following scene, they two start exploring the ninth floor and before long find a dubious room.
Inside, they track down a departed monkey that was additionally blood-let. They likewise see as the driller machine utilized by the killer. Upon getting once again to the police central command, Ling hears his supervisor telling Phantom to drop the case and spotlight exclusively on Ling, demonstrating that the division is dubious about him. After work, Ling gets back, and keeping in mind that he is chilling on the yard, he sees that Sonny’s toy is harmed with a few openings in it.
Surprised, Ling gets some information about who harmed his toy, and the young man answers ‘You Did’. Hearing this, he quickly heads to the storeroom and looks for his penetrating machine yet shockingly, it is missing. All of a sudden, he sees two bored openings on the wall and his very own blood print hand. The odd events further confound Ling, furthermore, however he makes an honest effort to review the past days, he fizzles. Until further notice, he simply conceals the imprints with paint.
Notwithstanding, the extremely next morning, he sees another horrendous hand shaped impression close to the past one, leaving him scared. He then, at that point, faces his loved ones also, cautions them to not take off from the house. Hazel requests the explanation yet Ling gives her none. Afterward, he goes to a specialist to find out when he will recover his memory as he is in perfect stress.
He makes reference to that he is a legitimate individual yet, nobody accepts him any longer. At the point when the specialist asks what concerns him, Ling answers; his family. He uncovers that quite a while back, his child suffocated in a lake in light of the fact that of his carelessness, and from that point forward, he hasn’t had the option to shake off that responsibility. Presently, all he thinks often about is the wellbeing of his loved ones, be that as it may, with a killer running wild, its hard to not stress.
Hearing this, the specialist proposes that he go through another blood test as well as a cerebrum check. At night, Ling visits the mortuary, where Apparition illuminates him that the penetrated openings on the casualties’ backs aren’t arbitrary. They seem to have a few examples, furthermore, are indistinguishable on both the bodies. Somewhere else, we see a female casualty, who has been kept inside a foul looking room.
 Just like different casualties, she has been penetrated on her back, and both her eyes are nailed. Some way or another, she figures out how to creep out of the neglected room yet when she arrives at the street, she is squashed by an approaching truck. A couple of seconds after the fact, Ling along with the police force show up at the scene and seal off the whole region.
Shockingly, even this time, the homicide has occurred close to Rugged island. Following this, Ling gets back to find his sister, Minnie, who has recently returned from the US. He is glad to see his sister however denies her too from going out of the house. That very night, Ling is contemplating the homicide situation when he sees his natural child’s drawing of a hare with a few dabs on it.
He rapidly contrasts it and that of the people in question’s opening example and an amazing miracle, it matches. The following day, a focused on Ling visits the specialist, what’s more, becomes acquainted with that his mind is ordinary however his blood contains a high centralization of the medication; Propranolol. The specialist further makes sense of that while Propranolol treats high circulatory strain, it additionally causes unsteadiness and momentary cognitive decline.
In fact, he hasn’t had the option to recapture his memory on account of the constant admission of the medication. This shocks Ling, as he doesn’t remember ingesting any medications. Afterward, Ling and Apparition go to the deserted room from before in order to view as a piece of information. In the hunt, Ling spots a disgusting looking man outside and starts pursuing him down the forest. In any case, Phantom, who sees no one, accepts that his companion has gone crazy.
Soon after, the two head over to Ling’s place. While they are having a beverage, Minnie strolls in with their young life photographs. Ling what’s more, Apparition go through the photographs when abruptly, Ling goes over an image of himself with four different children. Behind the image, it is referenced about the initial two casualties. Shocked, he checks the image once more, also, understands that 2 of the children are the people in question.
Sooner or later, Phantom has a confidential discussion with Hazel, what’s more, communicates his interests about Ling. Just then, Sonny strolls in with a few drawings, one of which contains a similar bunny drawing from previously. When Phantom sees it, he keeps it in his pocket. Afterward, while feasting, he shows the attracting to Ling, and asks about it, yet, the last option is similarly as dumbfounded.
Subsequently, a disheartened Phantom tempests out of the spot. The next day, at police central command, one of the officials approaches Apparition and shows him some photographs recuperated from the female casualty’s place. After checking them out, he sees a similar picture he found in Ling’s house. All of a sudden, he gets a dire news furthermore, heads to the funeral home. It turns out that Tai spent away last evening, what’s more, with this, their most obvious opportunity with regards to it is additionally gone to track down the killer.
Following this, Apparition drives Ling to Barbed Island and requests to become familiar with reality. Ling accepts that somebody is outlining him and that he is honest, yet Phantom doesn’t get it. All things considered, he helps Ling to remember the hare drawing and likewise shows him a similar photograph, uncovering that the casualties were really Ling’s experience growing up neighbors. Due to the dooming proof, Phantom notices that he can’t confide in his companion any longer.
He then begins contending with Ling, what’s more, incidentally gets pushed over the edge, bringing about a destructive fall. Acknowledging what he has done, Ling hurries to help his companion, yet even currently, Phantom attempts calling the specialists. This leaves Ling with no decision, so he hesitantly kills his companion. Later at home, he gets a call from the police, who ask about his whereabouts at the season of Phantom’s demise.
Ling claims to know nothing about the episode and untruths that he was at home. Nonetheless, the police division accepts he is ill suited for obligation and makes him take a long leave. Regardless of this, he stays focused on his central goal and chooses to capture the killer somehow. At some point, as Ling is spending some alone time close to a lake, he sees a similar man keeping an eye on him. Understanding that he is the killer, Ling immedaitely pursues him, and a serious pursue follows.
Sooner or later, the killer enters Sonny’s school and secures him. Be that as it may, as before long as Ling shows up there, he takes off. After the occurrence, Ling gets back and closes every one of the entryways while looking out the window. Minnie gets some information about the matter however Ling chooses to make sense of all that after it is finished. Some time afterward, he strolls higher up and finds the same photograph stuck on the storeroom.
He looks at it intently and understands that he had tormented one of the young men seriously before. He used to call him ‘transient kid’ and, surprisingly, called his mom ‘filthy’. All at once, Ling sees Sonny grinning at him from the gallery. Shockingly, the young child begins talking in an adult voice. Shocked, Ling inquires as to whether he is a phantom, however Sonny uncovers that he is, as a matter of fact, the transient kid.
It turns out that he has an infection called ‘Hostile to maturing affliction,’ which caused his body to quit developing after a particular age, while keeping his knowledge typical. Sonny further uncovers that he knows everybody from Ling’s family, since they share a typical dad. Following this, he begins describing about the past, when his mom brought him from Southeast Asia to track down his dad. Be that as it may, when they showed up at the dad’s home, they discovered that he had remarried a well off lady and had two kids.
Notwithstanding this, Sonny and his mother took a stab at persuading the dad to allow them to remain, yet he denied, compelling them to live in the city. From that day onwards, their lives started to crumble continuously. They got an obscure house to reside in, yet, his mom needed to sell herself ordinarily to meet the family necessities. Then, at some point, she died because of a venereal sickness, and it was Sonny without help from anyone else.
This is the point at which he chosen to involve his minuscule casing as a benefit. From the get go, he was embraced by a thoughtful family yet he could remain for a brief time frame or probably they would find his infection. To make due, he then started offering their infants to a kid dealer. In the end with time, he got a handle on the component of misdeeds.
Hearing this, a confounded Ling asks concerning why he is doing this and little Sonny answers that he essentially believes that Ling should encounter the sensation of being violated. He then uncovers that he isn’t doing this by itself, yet he has an accomplice. The killer is a similar individual Ling pursued before. His name is Mang, and he has Early-maturing infection.’ Along these lines, he ages rapidly, yet has very great insight and deftness.
Then, at that point, Sonny begins making sense of about the occurrence at Landmass Loft. He purposely took care of Ling with a ton of harmed cakes, making him lose his memory. He then, at that point, called Tai in the loft, professing to be lost. Before long, he messaged Ling, it is on the ninth to guarantee that his gun floor. At the point when Tai arrived from the start, Mang went after him, bored his body, and tossed him from the seventh floor of the loft.
He then, at that point, thumped Ling oblivious and hauled him to a similar floor. Ling questions why he wasn’t killed, and Sonny answers that he needs to detain him, since certain disciplines are more regrettable than death. He additionally uncovers that he killed the 3 casualties, to make sure he could approach him. Infuriated, Ling endeavors to kill Sonny yet as he is going to do as such, his significant other and Minnie mediate.
He frantically attempts to make sense of about the little man’s existence, however true to form, nobody trusts him. Sometime thereafter, George shows up at Ling’s house and transports him to the police headquarters for examination. George questions him about the killings however Ling stays quiet. Subsequently, because of absence of proof, he is delivered on bail. At some point, Ling hauls Sonny to a drifting stage in the ocean to frighten him.
Be that as it may, incidentally, it was Sonny’s arrangement from the start to get Ling out of the house with the goal that Mang would be able murder his loved ones. Hearing this, Ling surges back home yet it’s past the point of no return. Mang has as of now executed Hazel. Seeing his better half’s horrendous demise breaks Ling from within, furthermore, he begins crying wildly. Yet, soon, he gets up and surges outside for retribution.
When Ling gets out of the house, Sonny locks the entryway from inside. All of a sudden, Mang shows up with his penetrating machine, and the two beginning battling. While they’re busy, Sonny advances out. In the mean time, Ling figures out how to overwhelm Mang and ruthlessly bores him to death. Subsequent to killing one culprit, he goes out to kill Sonny, what’s more, at last corners him on a precipice.
 However before he can strike, the police appear with his sister. Ling has a go at making sense of that the youngster is a beast, however nobody pays attention to him. Presently, without any choices left, he continues to kill Sonny, however one of the police destroys him. In the last scene, we are shown that Ling has been imprisoned in a jail. He has been seen as at fault for 6 homicides, 2 of whom were his companions.  The film closes as Sonny sits close to the ocean, pleased that he effectively finished his central goal.
