民國年代，騙徒陳木昆善於假扮道士，一次惹禍，逃至五族房鎮。與此同時，木昆假借神仙呂洞賓之名行騙的事情，驚動了呂祖本尊，決定下凡懲治他。陰差陽錯下，洞賓失去法力，被迫滯留人間。洞賓及後以雷石之名伴隨木昆，以導化他踏上正途，期間竟破解鄉中不少奇案。一人一仙還遇上青樓女子白雪花，關係糾纏不清。鎮長辛虎退位，木昆暗中阻攔惡霸金士豪參選，新任鎮長辛正義亦針對士豪過往所為推行改革，為五族房鎮掀起連場風波……
Against a backdrop of the Republic of China era, fraudster Master Kwan is good at disguising himself as a Taoist priest. He flees to Five Races Town as he gets into trouble. Meanwhile, Kwan’s shenanigans – on the pretext of something to do with god Lu Dong-bin – have alarmed Great Master Luzu, who decides to go to the mortal realm to punish him. Through force of circumstance, Dong-bin is stranded in the mortal realm as he loses his mystical power. And then Dong-bin adopts Lui Shek as his new name while keeping Kwan company so as to help him get back on the straight and narrow. During the process, they solve bewildering cases in the village. A mortal and an immortal run into a prostitute called Pak Suet-fa, and they get entangled. Headman Sun Fu steps down. Kwan covertly prevents bully Kam Shi-ho from standing for election. Newly elected Headman Sun Ching-yee implements reforms as he deals with bad deeds committed by Shi-ho. A series of calamities is triggered in Five Races Town.
