Arrogant Flames(2011)

Arrogant Flames is a Thai drama that follows Plerng, a humble fisherman whose life changes overnight when his estranged grandmother suffers a heart attack. Twenty years earlier, Plerng's father abandoned his wealthy family to marry a poor woman, and the rift has never healed. When a car accident kills his father, Plerng makes a devastating choice: he donates his father's heart to save his grandmother's life, unaware she'll never know the truth. Forced to work at his family's diamond company to earn her forgiveness, Plerng must increase profits within three months or lose everything. As he navigates corporate intrigue and family jealousy, he finds himself drawn to Namfon, a colleague whose sister harbors feelings for him. The series builds toward an explosive revelation: when his grandmother discovers her heart donor's identity, will she finally accept the son she rejected?