Insanity (2014)

After the death of his son, Fan Kwok Sang develops a mental disorder and accidentally kills his wife, Wai Ling, in front of her mother. He was then committed to a psychiatric hospital and after three years Dr. Chow Ming Kit believes Fan is ready to be released . However, Fan can't adjust to his new life, especially with his Mother-in-Law paying often, troublesome visits. Dr. Chow begins to obsess over Fan's treatment to preserve his status and reputation.

Insanity is a mystery movie featuring Lau Ching-wan.

Insanity is currently streaming for free (ad-supported) on AsianCrush, Cineverse and The Roku Channel and it's also available on Amazon Prime Video and Midnight Pulp.

It is also possible to buy Insanity on Amazon Video.