At its simplest, a romantic drama is a narrative in which a romantic relationship is the primary plot driver, and the tone is predominantly serious, emotional, or melancholic. The key distinction from other romance sub-genres lies in its treatment of obstacles. In a romantic comedy, obstacles (a missed phone call, a silly misunderstanding, a competitive suitor) are temporary and light. In a romantic drama, the obstacles are profound: terminal illness, class disparity, war, betrayal, addiction, or the slow, painful erosion of trust.