劇情講述「每個角色的難戒之癮,皆來自人生的難解之結。」少女張凱希 (林奕嵐飾演) 為報復渣男王飛鵬 (張懷秋飾演),悄然接近他嗜酒成癮的妻子楊曼茹 (陳意涵飾演),兩人卻意外成為忘年之交,一步步走向失控人生。緝毒刑警陳啟明 (張孝全飾演) 在偵辦案件時與初戀曼茹重逢,同時陷入同袍之憾與舊情難忘的掙扎。與上癮無異的執念,使他們跌入各自深淵,在墜落的過程,陪伴成為彼此唯一的救贖。
Each character’s unbreakable addiction stems from unresolved life issues. To avenge herself against the scumbag WANG Fei-Peng, Casey ZHANG quietly approaches his alcohol-addicted wife, YANG Man-ru. Unexpectedly, they become close friends despite their age difference and embark on a path of drug abuse. Anti-narcotics officer CHEN Qi-ming, while investigating the case, reunites with his first love, YANG Man-ru. Their unresolved feelings lead to his guilt and struggle. Their obsessive attachments, akin to addiction, drag them into their own abysses.
张凯希(林奕岚 饰)的母亲遭受王飞鹏(张怀秋 饰)情感欺骗,凯希内心满怀愤懑,一度想要向对方的家人宣泄怨恨。在结识王飞鹏的妻子杨曼茹(陈意涵 饰)之后,她看清曼茹同样是婚姻里不知情的受害者,意识到迁怒无辜之人无法抚平伤痛。
刑警陈启明(张孝全 饰)长期侦查王飞鹏律所牵涉的重大案件,调查过程中意外重逢初恋曼茹。旧情再度浮现,但二人清醒认清当下现实与身份边界,克制内心悸动,恪守道德底线,理性面对遗憾,专注投身各自的责任与生活。另一边,凯希的男友Luca难以接纳凯希和他人界限模糊的相处,亲密关系矛盾不断激化。极端的占有欲让他萌生错误想法,试图以教唆凯希未成年妹妹贩毒的恶劣手段困住凯希。凯希未能察觉这段关系里扭曲的控制感,未及时果断远离不健康的情感模式,而酿成大祸,终身懊悔。