Hotshot filmmaker Pang Ho Cheung enlists his Love in the Buff leading man Shawn Yue to star in his latest production, Lacuna, opposite Zhang Jingchu (Flirting Scholar 2) as two strangers out to solve the mystery of what happened during their drunken night together. Helmed by Pang's writer partners Derek Tsang and Jimmy Wan (Lover's Discourse), the stylish urban rom-com is the anticipated theatrical feature in Pang's "4+1 Project" to nurture new directors, which also features other actors from the online shorts including Lawrence Chou, Zhu Yuchen, and singer Yoga Lin. One early morning, Shen Wei (Shawn Yue) and Tong Xin (Zhang Jingchu) are shocked as they wake up in bed together in a furniture mall, not knowing each other and without a clue why they are even there. Out of embarrassment, the two quickly flee the scene and go their separate ways. Xin realizes that the big stash of cash her boss entrusted to her is missing. Meanwhile, Wei has lost the company car and become the laughing stock of his co-workers when photos of his shenanigans begin spreading online. In their desperation, Wei and Xin receive calls from the police with the news that the pet they reported missing last night has been found, and that brings them together again on a journey to find out all about their drunken escapades...