It is a drama about disputes inside a large family, revolving around a murder and a police investigation. The title is a play on the expression "blood is thicker than water." Their familial relationships are weak due to the disagreements. When a family member dies in a suspicious manner, everyone's true colors are going to be revealed. Yi, the oldest brother, and Pete, the second brother, endeavor to uncover the truth. Patsorn and their mother, Cris, are the most likely culprits. Both of them must establish their innocence. The more Yi and Pete probe, however, the more dirt they uncover on the family, until everyone becomes a suspect.