Can the logical brain mix with volatile emotions? Han Seung Joo is a star neurosurgeon who is renowned for his extraordinary memory. To him, the world is very clear-cut and logical. But his strong personality frequently places him at odds with his fellow neurosurgeon, Cha Jae Hwan, who is the son of the hospital director. When they both fall for Joo In Ah, an endocrinologist who is obsessed with hormones, they take competition to a whole new level.