阿成是一名在這棟大廈工作的保安，五年來，他每天的工作就是在深夜時分，巡查這棟早已人去樓空的工業大廈。這裡曾經是個熱鬧的工業集中地，但隨著時代的變遷，許多公司搬遷或倒閉，大廈逐漸變得冷清。如今，除了幾家還在勉強營運的小公司，其他樓層幾乎都已經空置。
然而，這棟大廈中有一層樓與眾不同，那就是十二樓。那層樓的燈光從未熄滅，即使是深夜兩三點，整層樓依然明亮得像是白晝。阿成起初並未多想，以為是某家公司忘了關燈，但隨著日子一天天過去，他發現這燈光的存在並不尋常。
有一次，他忍不住翻看了管理處的租戶記錄，卻驚訝地發現，十二樓根本沒有任何租戶登記。管理處的老員工告訴他：「那層樓早就沒人了，燈壞了也沒人修，乾脆就一直亮著吧。」可是，這解釋並不能說服阿成。因為他知道，這棟大廈的電費由各租戶分攤，沒有人會願意為一層空置的樓層支付電費。而且，那燈光並不像是壞掉的電燈，反倒像是有人刻意保持開著。
某個深夜，阿成如往常一樣進行巡樓工作。他搭乘升降機逐層檢查，當升降機緩緩上升到十二樓時，他心裡莫名感到一陣寒意。門打開的一瞬間，他愣住了。
十二樓的走廊一片潔白，燈光明亮得刺眼。地板被擦得一塵不染，甚至反射著燈光的光芒；牆壁乾淨無瑕，就像剛粉刷過一般。這樣的整潔與大廈其他樓層的破舊形成了鮮明對比。
他小心翼翼地走出升降機，腳步聲在空蕩的走廊中顯得格外清晰。他的目光被吸引到走廊盡頭的一扇門，那是一扇半掩著的木門。門內傳來清晰的聲音，是鍵盤敲擊的聲音，「啪、啪、啪」，節奏穩定而不間斷。
「有人在加班？」阿成心裡這麼想，但又感到不對勁。這麼多年來，他從未見過有人進出這層樓，也從未聽說過有新的租戶入駐。他壓低聲音說：「我是保安，巡樓。」然而，門內並未傳來任何回應，那鍵盤聲依然持續著。
阿成猶豫了一下，最終還是選擇退回升降機。他按下關門鍵時，感覺到背後有一股涼意襲來，但他沒有回頭看。他知道，有些事情不該過於探究。
回到更亭後，他立刻調出了十二樓的閉路電視畫面。然而，螢幕上的畫面卻讓他更加困惑——十二樓的監控畫面竟然一片漆黑，完全看不到任何燈光。阿成揉了揉眼睛，再三確認時間和畫面，但結果依然如故。明明他剛才親眼看到十二樓燈火通明，可閉路電視上卻什麼也沒有。
第二天，他再次向管理處詢問十二樓的情況。負責管理的大叔皺著眉頭說：「我都跟你講過了，那層樓早就沒人了。你要是覺得奇怪，不如別上去好了。」
阿成聽完後心裡更加疑惑，但也不敢再多問。他隱隱覺得，有些事情不是自己該知道的。
幾天後的夜晚，他再次巡樓時發生了一件奇怪的事。當他搭乘升降機準備上十二樓時，升降機卻突然跳過了那一層，直接停在了十三樓。他試著按下十二樓的按鈕，但按鈕似乎失靈了一般，毫無反應。他只能無奈地返回更亭。
當晚，他躺在值班室的小床上輾轉反側。腦海中一直浮現出那扇虛掩的門和門內傳出的鍵盤聲。他越想越不安，最終決定再次嘗試進入十二樓。
凌晨兩點，他悄悄走到樓梯間，打算爬樓梯上去。然而當他推開通往十二樓的防火門時，一股濃重的霧氣迎面撲來。他下意識地捂住口鼻，但霧氣卻迅速消散，只剩下刺眼的燈光照亮整個走廊。
那扇熟悉的木門依然虛掩著，鍵盤聲也依舊清晰可聞。阿成鼓起勇氣走上前，用力推開門。
房間裡空無一人。只有一台老舊的電腦擺在桌上，螢幕發出微弱的藍光。而那鍵盤聲……竟然是自己自動敲擊發出的！阿成倒吸了一口涼氣，下意識地向後退了一步。
突然間，電腦螢幕亮了起來，上面出現了一行字：「不要干涉。」
阿成僵住了。他感覺全身冷汗直流，但雙腿卻像被釘在地板上一樣動彈不得。他盯著螢幕上的字，一時間不知道該如何反應。
「請離開。」螢幕上又出現了新的文字。字體閃爍著，就像是在警告他。
阿成咬緊牙關，終於鼓起勇氣轉身跑出房間。他一路狂奔下樓梯，直到回到更亭才停下腳步。他喘著氣，回頭看向監控螢幕上的十二樓畫面——依然是一片漆黑。
自那天起，阿成再也沒有踏足過十二樓。他也不再試圖尋找答案。他知道，有些事情注定無法解釋，而有些秘密則永遠不該被揭開。
每當夜深人靜時，他坐在更亭裡，看著監控螢幕上的黑暗畫面，但腦海中卻總會浮現出那扇虛掩的門，以及門內傳來的鍵盤聲。「啪、啪、啪」，那聲音似乎永遠不會停止，就像是某種未知力量在運作著。而十二樓的燈光，也將永遠亮著，為某種神秘而不可知的秩序服務……
English Version
Ah Shing had worked as a security guard in the old industrial building for five years, long enough to witness its gradual decline from a once-busy hub of factories and offices into a near-forgotten structure where only a handful of struggling companies remained, leaving most of the floors abandoned and silent, yet among all the empty spaces within the building, there was one that refused to follow the same pattern—the twelfth floor, a place that defied explanation in a way that unsettled him more with each passing day unlike the rest of the building, where lights were routinely switched off after hours, the twelfth floor remained brightly illuminated at all times, even in the deepest hours of the night when no one should have been present, and at first, Ah Shing dismissed it as a simple oversight, assuming that some tenant had forgotten to turn off the lights, but as days turned into weeks and weeks into years, he realized that the lights never changed, never flickered, never dimmed, maintaining a constant brightness that felt deliberate rather than accidental, and when curiosity finally drove him to check the tenant records, he discovered something that made the situation even more unsettling—there were no registered occupants for that floor, no leases, no documentation to explain why it remained active, and when he brought this to the attention of the management staff, their response was vague and dismissive, insisting that the floor had long been vacant and that the lighting system was likely faulty, though this explanation failed to convince him, because he knew that electricity costs were shared among tenants and no one would willingly pay for a fully lit, unused floor, and more importantly, the quality of the light itself did not resemble a malfunction but rather the controlled illumination of a space in use; one night, during his routine patrol, he decided to investigate further, stepping into the elevator and allowing it to carry him upward floor by floor until it reached twelve, and as the doors opened, he was met with a scene that contradicted everything he had come to expect from the building, the corridor before him immaculate and gleaming, its floors polished to a reflective shine, its walls pristine as if freshly painted, the entire space radiating a brightness that felt almost sterile compared to the worn and decaying environment elsewhere, and as he stepped out cautiously, the sound of his footsteps echoed unnaturally in the empty corridor, drawing his attention toward a half-open wooden door at the far end, from which a steady, rhythmic typing sound emerged, the sharp tapping of keys echoing through the silence with mechanical precision; assuming that someone might actually be working there despite the lack of records, he called out, identifying himself as security, but received no response, the typing continuing uninterrupted as though his presence had not been acknowledged, and after a moment of hesitation, a cold sensation creeping along his spine, he chose not to enter, retreating instead back into the elevator, unable to shake the feeling that he had narrowly avoided something he did not fully understand; once back at the security station, he immediately checked the surveillance cameras for the twelfth floor, expecting to confirm what he had seen, but the monitor displayed only darkness, the entire floor appearing unlit and empty as though it did not exist in the same state he had just experienced, and the contradiction between his own eyes and the camera feed left him deeply unsettled, unable to reconcile the two realities; the following day, he questioned management again, pressing for clearer answers, but they repeated the same dismissive explanation, advising him not to concern himself with matters that did not affect his duties, and though he outwardly accepted their response, the unease remained, growing stronger with each passing night; days later, during another shift, he noticed a new anomaly—the elevator began skipping the twelfth floor entirely, moving directly from eleven to thirteen without stopping, regardless of how many times he pressed the button, as though the system itself had been altered to prevent access, and this change only deepened his suspicion that something was being deliberately concealed; unable to let the matter rest, he resolved to reach the floor by another means, and in the early hours of the morning, he entered the stairwell, climbing cautiously until he reached the fire door leading to the twelfth floor, and when he pushed it open, a dense mist rushed out to meet him, momentarily obscuring his vision before dissipating to reveal the same brightly lit corridor he had seen before, unchanged and waiting, with the half-open door at the end still emitting the steady rhythm of typing; this time, driven by a mixture of fear and determination, he approached the door and pushed it open fully, revealing a room that appeared empty at first glance, containing only an old computer on a desk, its screen glowing faintly blue, and as he stepped closer, the source of the typing became horrifyingly clear—the keyboard was moving on its own, the keys pressing down in rapid succession without any visible input, producing the sound he had heard from the corridor, and before he could react, the computer screen flickered to life, displaying a message in stark, unambiguous text: “Do not interfere,” and the words seemed to pulse with an authority that froze him in place, a second message appearing moments later: “Leave,” its letters flickering as though reinforcing a warning that went beyond mere suggestion; a wave of cold sweat washed over him as he struggled to regain control of his body, and with a sudden surge of instinct, he turned and fled the room, running down the stairs without looking back until he reached the relative safety of the security station, where he immediately checked the monitors once more, only to find the same black screen showing no sign of light or activity on the twelfth floor; from that night onward, he made a conscious decision never to return, understanding that whatever existed on that floor operated beyond his comprehension and beyond the boundaries of what he should attempt to understand, and though the building continued to function as it always had, with tenants coming and going and the passage of time slowly eroding its structure, the twelfth floor remained unchanged, its lights perpetually on, its presence quietly asserting itself within the building’s hidden layers, and even now, as he sits in the security booth during the silent hours of the night, watching the blank feed of the surveillance monitor, he cannot escape the memory of that half-open door and the relentless sound of typing that seemed to echo endlessly, as if something within that space continued to work tirelessly toward a purpose unknown, maintaining an order that did not belong to the world outside, and serving as a reminder that some places are not meant to be observed, only acknowledged from a distance, their existence accepted without question, because to seek answers may be to invite something that should never be disturbed.