[a][2][3] Starring Park Yoo-chun, Shin Se-kyung, Namgoong Min and Yoon Jin-seo, it aired on SBS on Wednesdays and Thursdays at 21:55 for 16 episodes from April 1 to May 21, 2015.

The lead detective on the case, Oh Jae-pyo (Jung In-gi) realizes that the now-comatose daughter Eun-seol is the sole surviving witness.

She has also gained the unique ability to "see" smells as visible colors and shapes, and can even trace where people have been because their lingering scents are like a trail.

On the other hand, Moo-gak had been so traumatized by his sister's death that after two months of no sleep and constant pain, he'd fainted and was clinically dead for ten days.

After a model (Park Han-byul) turns up dead, seemingly another victim of the Barcode serial killer, Moo-gak joins the investigation headed by Lieutenant Yeom Mi (Yoon Jin-seo), and he zeroes in on two possible suspects: the model's boyfriend, chef Kwon Jae-hee (Namgoong Min) and her doctor (Song Jong-ho).