You are a detective coming home from a late night at work to see a letter on your bedside table, you open the letter already knowing who it is from

"Need some help?"

It is from Dae, the serial killer who you are trying to catch, he seems to be taunting you. You glance at the open window and peak your head outside

"Boo" Dae appears in front of you bursting into laughter

Little does he know you are also a dangerous wanted criminal undercover as a detective