捕快易超调查杀人案，查出真凶是盐帮少帮主吕高阳，并将其抓捕归案。吕高阳承认罪行，易超将他移送州府被判斩立决，在行刑时易超发现人犯被调换，他排除阻力追踪调查，几经周折最终挖出幕后黑手，将一干恶人绳之以法...
At17:00everyday,Andrew,amiddle-agedman,driveshomefromworkthroughMelbourne’soutersuburbsinpeak-hourtraffic.Occasionally,heoffersalifthometoayoungercolleague,David.Overayear,theirtentativesmalltalkgiveswaytoawarmfriendshipandopenconversationwithintheconfinesofthevehicle,incrementallyrevealingtheirlives.Onemaywonderwhatathree-hourfilm,setalmostentirelyinacarandshotwithafixedcamerafromtheback,candeliver?Theanswerisanunexpectedlyengagingandentertainingobservationoftherhythmsofdailylife,andacatalogueofsuburbanworries.Insensorialterms,ThePlainschartsthepassageoftimeastheseasonschange.Thepitter-patterofrainandthefamiliarcocoonofthecarprovideasenseofcomfortandsafetyfromtheoutsideelements.Thecaristheliminalspacebetweenworkandhome,asthedayispondered,thenightplanned.Documentaryelementsexistbeyondthewindscreen,asafictioncoursesthroughthevehicle.ThePlainsisaroadmovieunlikeanythingyouhaveseenbefore.
高宇蓁饰演性工作者，为了实现梦想，被卖到国外从事性工作。电影除了是对性工作者这一社会边缘群体的关注，也阐述女性议题。黄冠智饰演高宇蓁的弟弟；段钧豪、黄冠智饰演经常光顾茶室的警察；郭耀仁饰演茶室围事、也是妈妈桑的姘头；蔡嘉茵饰演妈妈桑。众人将共同演绎大时代底下边缘角落的小人物故事。
