Anyamanee is a beautiful girl brought up in family that only honors men, which make her proud of what she has cause she got it with so much difficulty. She meet Guerkhun, a man who warms both body and heart, whom is ready to give a warm light to a woman who is like a diamond in his heart, but love life isn't that easy. When two families' business problems get involved including the death of Anyamanee's brother, make Guerkhun become her first suspect, because of his past relationship with her sister-in-law which ended a long time ago has come back again. Will the trust prevail in this situation? Adapted from the novel Nam Phet” (น้ําเพชร) by Piyaphon Sakkasem (ปิยะพร ศักดิ์เกษม).