Set in Seongsu-dong, the trendy epicenter of branding and creative agencies in Seoul, the drama follows Kang Na-eon, the youngest and most ruthless marketing team leader at Seongsu Agency. Known for her unyielding work ethic, perfectionism, and relentless ambition, Na-eon has sacrificed friendships and romance to climb the corporate ladder, making numerous enemies along the way. In stark contrast stands So Eun-ho, the agency's oldest, easygoing, and principled intern. Eun-ho advocates for ethical marketing, sincerity, and consumer welfare, frequently clashing with Na-eon's cutthroat, profit-driven methods. Despite their philosophical differences and strained working relationship, fate intervenes when an unexpected and mysterious kiss leads to their souls swapping bodies. Now trapped in each other's lives, Eun-ho must navigate the ruthless, high-stakes corporate world in Na-eon's cutthroat shoes, while Na-eon is forced to endure the humble, vulnerable existence of an intern. As they struggle to keep their identities a secret and maintain their agency's high-profile marketing campaigns, they uncover a dangerous conspiracy targeting Na-eon's career and life, forcing them to collaborate, understand one another's perspectives, and unravel the genuine feelings budding between them.