A Murderer's Guide to Memorization) is a 2017 South Korean mystery thriller film directed by Won Shin-yun.

After killing his abusive father, teenage Byeong-soo (Sul Kyung-gu) begins to believe there are people who deserve to die.

After killing a woman, he gets into a car accident suffers a head injury, resulting in degenerative Alzheimer's disease.

He stops killing, resumes his job as a veterinarian, and continues caring for his daughter Eun-hee (Kim Seol-hyun).

After multiple visits to the local police station (as he forgets his address), Byeong-soo strikes up a friendship with policeman Byeong-man (Oh Dal-su).

Byeong-soo goes to a poetry class, where his poetic depictions of murders attracts classmate Jo Yeon-joo (Hwang Seok-jeong).

After ascertaining the blood sample is human, Byeong-soo anonymously calls the police, describing the encounter and the car's make and license plate.

After Byeong-man tells him about the license plate's owner, Byeong-soo realizes Tae-joo is the killer who uses his daughter to taunt and threaten him.

Fearing for his daughter's safety, Byeong-soo orders her to stay with his sister Maria (Gil Hae-yeon) at her convent.

Byeong-soo recalls almost strangling Eun-hee, mistaking her for his wife, and becomes convinced that he might have killed his daughter in a fit of insanity.

Eun-hee, having learned from Tae-joo earlier that her mother's body was found in the bamboo grove, is terrified of her father.

According to its distributor Showbox, the film was scheduled to open in North America on 8 September 2017, two days after its domestic release.

[10] Memoir of a Murderer was also shown in the Thrill section at the 61st edition of the BFI London Film Festival, which runs from 4–15 October.

It includes 10 more minutes of footage and has had its rating changed from 15 to R.[12] Primarily, Tae-joo's corpse disappears after he confesses to Eun-hee at the cabin.

Back in the jail, the investigator decides to let him go, since the murder cases have long expired and considering the fact that Byeong-soo has Alzheimer.