Queen Mantis

Jung I Sin is a serial killer with the nickname of the Mantis. She brutally murdered 5 men 20 years ago. Her son is Cha Su Yeol. He has loathed his mother for his entire life. He now works as a police officer. One day, a murder case takes place. The murder seems to be a copycat crime copied from Mantis. To catch this culprit, Cha Su Yeol enlists the help of his mother, Jung I Sin.

(Source: AsianWiki)

~~ Remake of the French online series "The Mantis" (La Mante) [2017].