Mr. Smart considers himself the smartest man of Hong Kong. To this assessment, his mother takes strong exception. When he comes home from a seafaring job, he is angered by the fact his mother has rented out his room to a teacher. It takes, some great effort by his sister to concile him. Then her driver boy friend offends Mr. Smart. But soon they make up. The teacher talks Mr. Smart into starting a quick food shop. Thanks to the patronage of the students, the shop has its ups and downs. Then Mr. Smart discovers the students are making fun of him... (Deltamac DVD)