Yoon Jeong dreams of a brilliant life driven by ambition and achievement, while her older sister Eun-ah wishes only for a simple, peaceful existence. Their lives become entangled with Cheol-yoon, a man bound by family expectations, and Joo-hwan, Jeong’s lifelong friend who has always stayed by her side. As their emotions intertwine, fate traps the four in a web of love, desire, and regret, leaving behind wounds that cannot be undone. The weight of secrets, guilt, and conflicting desires ultimately leads them toward an irreversible tragedy—one that casts its shadow onto the next generation.