Doh I-Hyeon is the ultimate corporate workaholic, but he hides two secrets: he’s a somewhat defective omega and he suffers from prosopagnosia—the inability to recognize faces. After a blurry, drunken one-night stand leads to an unexpected pregnancy, I-Hyeon decides to keep the baby and brave single parenthood in secret. But his carefully constructed walls start to crumble when his superior, Seo Jeong-Un, begins a relentless pursuit. Jeong-Un is charming, persistent, and strangely familiar, but to a man who can’t recognize a face, his flirtations are just another workplace distraction. Can Jeong-Un break through I-Hyeon’s "iron wall," or will I-Hyeon’s condition keep the father of his child a mystery forever?