Mentally challenged Ah Wong is confused when his childhood friend Catherine Wong grows up and catches the eye of her boss' son Michael. To add to the confusion, her coworker Angel is also interested in Michael.

Ah Wong is a 30-year-old man with an IQ of a little boy; however, he seems to find ways to make everyone around him happy and lucky. Ah Wong grew up with his best friend Catherine, who he always called her "Little Wife". Throughout their childhood years, Ah Wong relied very much on Catherine until she decided to study in New York, thus the two of them had to separate for four years. Ah Wong gave all his savings to Catherine, as he thought he would marry her when she returned. When Catherine graduated and came back to Hong Kong, she started working at Chung Kam-Wing's firm. It is through work where Catherine meets Michael, Kam-Wing's son. To complicate matters, their coworker Angel is also interested in Michael.—Lam