How was the agent able to find him so quickly whereas the whole police in Korea couldn't?
And was it at all plausible and realistic that the agent could locate him so easily even with gadgets at his disposal whereas the whole police force couldn't? Or was he just lucky on that front and it was a matter of coincidences?
How did the killer never raise suspicion and again since he was the school bus driver, how did no one know where he lives etc so he could be apprehended, and as was raised before, if he was already suspected in a series of murders, how was he allowed to be a school bus driver?