"Once infected, you'll be lovesick"
A mysterious virus spreads out. Anyone infected feels the emotion of love, and the emotion amplifies until it kills the person in love. The pessimist Taek-seon, who likes nothing in life, is infected, and the researcher Gyun reaches her out to test her the medicine that he's developing. Soon Gyun finds out Taek-seon has special antibody, but Taek-seon slowly feels love to Gyun. Is this a real love or just a virus?
Ok Taek-seon

Lee Gyun

Kim Yeon-woo

Nam Su-pil

Professor Seong

Director of Research Institute

Young-hee

Jeong-hun

Ms. Yeom

Na Jeong-bae

Taek-seon's Mother

Gyun's Mother
Ji-seon

Yi-ju

Manager Kim

Doctor 1

Doctor 2

Cop 1

Cop 2

Young Taek-seon