Detective Zero (2019)

"Rekihiko Tokiya (Ikki Sawamura) is an excellent detective in Kyoto. While he chases a suspect, Rekihiko Tokiya falls into a water storage pool at an abandoned factory. He wakes up in a hospital room. Rekihiko Tokiya is stunned that he cannot remember anything from the past 20 years. He is 51-years-old, but he cannot remember anything from the age of 31 when he started work as a detective. He is a divorcee, but he has does not remember his ex-wife. Rekihiko Tokiya’s personality also changes. He was once a confident person, but he is now timid and lacks confidence. His sense of justice is still strong. Rekihiko Tokiya resumes work as a detective, but he deals with cases differently than in the past." - AsianWiki