Former lovers Qin Yun and Lü Shang unexpectedly reunite through a workplace project after being apart for five years. Determined to maintain clear boundaries, Qin Yun establishes rules for their interactions. However, as they work closely together day after day, she finds herself falling for Lü Shang again and his gentle, protective nature. Soon, romantic rivals stir up trouble, and a series of workplace sabotage incidents erupt. Facing one crisis after another, they stand by each other and finally uncover misunderstandings buried in the past. Letting go of their emotional barriers, they rekindle their deep love, overcome the regrets of five years apart, and choose to spend the rest of their lives together.