Meanwhile, a corrupt policeman named Lung threatens Tai, his neighbour and a classmate of Yu Ting who is secretly in love with her, demanding he vacate his home or face false drug possession charges.

The video spreads online, causing public outrage and bringing personal details about Lung to light, which leads him to seek a hideout and Yu Ting is revealed to be his daughter on internet forums.

[1] Lee later met Kurt Chiang, who joined the project as the writer and completely rewrote the screenplay, transforming it into a school-themed mystery based in Hong Kong.

[1][7] The revised screenplay was completed in 2016, and Lee presented it at the Hong Kong - Asia Film Financing Forum that same year, but it was still rejected by investors as there was deemed to be no market in mainland China.

[10] The film was publicly announced in February 2018, with Chapman To, Huang Lu, Alan Luk, and Griselda Yeung revealed as the main cast, and Herman Yau as the producer.

Lee Cheuk-pan stated that he envisioned the story taking place in a tong lau from the outset, as he found it to be the most representative of Hong Kong, and he deliberately set both the first and final shots of the film inside the building.

[17] The production crew identified eighteen words starting with "G", including "Guts", "G cup", "Gun", "Girdle", "Gastric cancer", "Giving head", "Gonorrhea", "Goon", "G Major", and "Gustav Klimt", each of which relates to specific plot points.

[23] Elizabeth Kerr of The Hollywood Reporter considered the film a vivid but bleak debut by Lee Cheuk-pan, examining the corrupt and morally decaying society of Hong Kong, and found it engaging overall despite its convoluted storytelling and grim characters, particularly praising the performances, especially that of Chapman To.

[5] Edmund Lee of South China Morning Post gave the film 3.5/5 stars, considering it more as a collection of ideas and critiques presented with art-house flair than as a cohesive story, but still regarded it as a stylistically impressive effort that captures the frustrations of Hong Kong's youth in the wake of the Umbrella Movement and deserves recognition for its departure from traditional cinema.

[24] Fionnuala Halligan of Screen Daily lauded the film's cinematography and strong performances, and although she critiqued its intricate structure and distracting reliance on the letter 'G', she nonetheless found that it presents a brutal tale of corruption and depravity that offered an encouraging glimpse into the future of Hong Kong cinema.

Pryor of Cinapse called the film a deeply depraved yet cleverly crafted thriller that presented "a dark, borderline misanthropic view of humanity", exploring the sordid complexities of the people in Hong Kong, through the strong performances particularly from Chapman To and Huang Lu, along with skillfully woven narrative threads, making it a challenging but rewarding cinematic experience.

[26] Sek Kei, writing for The Stand News, offered a rather negative review, labeling the film as an ambitious yet chaotic black comedy that, despite its creative blending of genres and moments of brilliance and humour, is hindered by a disjointed narrative and illogical plot, leading to an incomplete and overly gimmicky project that ultimately feels "out of control".

[27] However, Ben Lam, reviewing for Hong Kong Inmedia, expressed an opposite view, calling the film "almost flawless" and complimenting its skillful blend of local themes with Japanese cinematic characteristics, addressing pressing social issues through a complex narrative structure and compelling performances, ultimately leaving a profound impact on viewers regarding generational and political tensions in Hong Kong.

[28] Emilie Choi of Ming Pao also praised the film as "bold and innovative", critiquing societal structures through fragmented storytelling and complex character dynamics, ultimately highlighting the struggles and resilience of youth in a chaotic adult world.