Bok-Soon (Kim Go-Eun) lives with her younger sibling. She runs a street stand. Bok-Soon is slow, but when people angers her she goes crazy. That's why she is known as the "crazy woman".
One day, cold-blooded killer Tae-Soo (Lee Min-Ki) appears in front of her. To hide his secret, he kills Bok-Soon's younger sibling. Bok-Soon then goes after Tae-Soo for revenge, but Tae-Soo goes after Bok-Soon.