一個「人有相似」的網站，讓兩位原本各不相干，外貌卻極為相像的陌生人聯繫上。律師樓合夥人高收成在網上發現失聯多年的舊戀人俞風，徵聘與自己相似的男人作短期男伴。收成私下接觸長相一模一樣的應徵者巫祺男，二人更秘密協議交換身分兩週，由收成充當俞風「愛的替身」；失敗小人物祺男則冒充收成，周旋於妻子利梓楹與岳父利冠鏗之間，應付律師樓每個危機。隨着互換身分期限將至，這對雙生人才驚覺彼此的人生軌跡早已不似預期……
一個「人有相似」的網站，讓兩位原本各不相干，外貌卻極為相像的陌生人聯繫上。律師樓合夥人高收成在網上發現失聯多年的舊戀人俞風，徵聘與自己相似的男人作短期男伴。收成私下接觸長相一模一樣的應徵者巫祺男，二人更秘密協議交換身分兩週，由收成充當俞風「愛的替身」；失敗小人物祺男則冒充收成，周旋於妻子利梓楹與岳父利冠鏗之間，應付律師樓每個危機。隨着互換身分期限將至，這對雙生人才驚覺彼此的人生軌跡早已不似預期……
A “doppelgangers” website has facilitated the connection between two complete strangers that look like identical twins. Law firm partner Ko Sau-shing tracks down his former lover Yu Fung, whom he has not contacted for ages, online, and Yu Fung is looking for a part-time boyfriend with a similar appearance to him. Sau-shing arbitrarily approaches applicant Mo Kei-nam, who is a dead ringer for him. The duo also covertly agree to swap identities for two weeks. Sau-shing plays the role of Yu Fung’s “substitute lover”, and deadbeat Kei-nam disguises himself as Sau-shing while simultaneously dealing with his wife Lee Chi-ying and father-in-law Lee Kwun-hang as each and every crisis at the law firm is handled by him. While the identity swapping deadline looms, this pair of lookalikes are eventually shocked to realize their mutual life trajectories are already different from their expectations.
