「白色大樓」曾是柬埔寨首都金邊的標誌性建築物。在60年代，這楝大型住宅大樓是當年柬埔寨現代化的象徵。導演就是在那裡的其中一個單位長大的。經歷過歲月的洗禮，殘舊的大樓要面臨拆卸，於是他就把握這個機會，記錄住客們在搬遷前最後的生活、懷緬過去的點滴。電影對老百姓的仔細觀察，能帶出慘痛的國家歷史之餘，亦道出大家對未來的疑惑。這部紀錄片是柬埔寨新勢力在國際影壇冒起的有力證明。

Last Night I Saw You Smiling chronicles the final days of Phnom Penh's White Building, a Bauhaus-style tenement block which was about to be demolished when the documentary was made – an act which would remove from the Cambodian capital a symbol of Norodom Sihanouk's internationalist aspirations for his country in the 1960s. Having grown up with his family in the White Building, Kavich Neang offers a first feature filled with delicate observations of ordinary people braving for sweeping changes in their lives, in a film which is at once about architecture, history and how human beings navigate their memories in hallways and rooms that have become all but a memory.