The one-hour 52-minute Thrishanku, is about two young couples who eloped to Mangaluru. Mature and immature relationships are the two types shown by the director.
The plot of the movie is a kind of cat-and-mouse game as Sethu (Arjun Ashokan) and his relatives are in search of Sumi (Zarin Shihab) and her lover while Megha’s (Anna Ben) dad (Krishna Kumar) gets to know about Sethu.