出身将门的原家大小姐被人劫持，醒来后失去记忆，性情大变，为逃避婚约离家出走，化名阿原，女扮男装成为沁河县的小捕快。与此同时，贵公子景辞在送心上人和亲的途中遭人暗害，侥幸生还后，也以县尉的身份来到沁河，成为阿原的同僚，暗中守护阿原。阿原专心一意惩诫奸恶，力保一方百姓安宁。树欲静而风不止，小县城凶案频起，景辞、阿原抽丝剥茧，步步逼近真相，却因重重阻力难以为继。不久，阿原发现她并不是真正的原家大小姐，景辞也不仅仅是一名小县尉。当他们的离奇身世先后揭开，二人感情遭遇严峻考验。阿原跟景辞决裂，另嫁他人之际，京城又一宗谋杀案，疑点直指阿原，令她身陷囹圄。景辞为救阿原，以病弱之躯拨开迷雾，找出了幕后指使者，带阿原远离风波。
In the first year of Later Liang lived Yuan Qingli, the daughter of a general. While on the road to a nunnery to reflect and meditate, she is abducted and knocked unconscious. After her rescue, Yuan Qingli wakes up days later without her memories and with a new personality. To escape from her own wedding, she dresses as a man and becomes a constable of Qinhe County.
Zhao Wang's adopted son Jing Ci is ambushed while accompanying his childhood friend Ma Fengmian to be wed. After being rescued by Liang Wang, Jing Ci assumes the identity of a Liang official and discovers clues to a conspiracy within the palace courts. To pursue his investigation, Jing Ci goes to Qinghe on business and takes a position as a county official. The sickly Jing Ci and rookie constable Yuan Qingli join hands to unravel layers upon layers of long-standing corruption. In a quest for the truth, Yuan Qingli also learns her real identity.
出身將門的原家大小姐被人劫持，醒來後失去記憶，性情大變，為逃避婚約離家出走，化名阿原（陳鈺琪飾），女扮男裝成為沁河縣的小捕快。與此同時，貴公子景辭（於朦朧飾）在送心上人和親的途中遭人暗害，僥倖生還後，也以縣尉的身份來到沁河，成為阿原的同僚，暗中守護阿原。阿原專心一意懲誡奸惡，力保一方百姓安寧。樹欲靜而風不止，小縣城兇案頻起，景辭、阿原抽絲剝繭，步步逼近真相，卻因重重阻力難以為繼。不久，阿原發現她並不是真正的原家大小姐，景辭也不僅僅是一名小縣尉。當他們的離奇身世先後揭開，二人感情遭遇嚴峻考驗。阿原跟景辭決裂，另嫁他人之際，京城又一宗謀殺案，疑點直指阿原，令她身陷囹圄。景辭為救阿原，以病弱之軀撥開迷霧，找出了幕後指使者，帶阿原遠離風波。
