Adapted from a popular comics serial, Hindi Nahahati Ang Langit tells the story of the complex relationship between stepsiblings Noel and Melody. Noel is the wealthy son intolerant of his father's new partner Agnes and her daughter. From the start, the two children are antagonistic against each other, and their squabbles continue into adulthood and their parents' tragic demise. Noel appoints himself Melody's legal guardian and exercises his authority over her, driving her to rebel and throw herself into the arms of aristocratic Roland. Equally irked by Noel's romance with naive Cynthia, the sister of a college friend, Melody sets up her own company to rival Noel's firm. As fate would have it, the two rivals are hired to work together on a big contract that forces the two to actually confront the source of their resentment and admit a genuine affection and respect for each other. Full of pride and unwilling to back down, Roland has other plans that could spell their ruin as well as alerting Cynthia to their relationship.