David Lee’s second film after the little-seen teen horror thriller Yes, I Can See Dead People, Insanity is produced and co-written by Derek Yee, and tells of Fan (Lau Ching Wan), who became a neurotic shell of a man following the death of his child, and frequently lets out his anger and grief on his wife Wai Ling (Michelle Ye), forbidding her to go out and suspecting her at every turn. Until one night, in a fit of jealous rage, he accidentally kills her by pushing her out of a window. He’s declared insane in court and committed to a psychiatric hospital, where he’s placed under the care of Dr. Chow (Huang Xiaoming) a young and promising doctor who is fast rising to the top of his field, though he’s neglecting his girlfriend Bo Yi (Fiona Sit) in the process. Three years later, Chow vouches for Fan’s release against the advice of his colleague Dr. Lui (Alex Fong), declaring him cured. Life on the outside proves difficult for the former madman, as his former mother-in-law (Paw Hee Ching) keeps harassing him and guilt remains vivid. One night, while attempting to commit suicide, he accidentally kills a homeless junkie. But Dr. Chow, who’s close to becoming hospital director, is determined to safeguard his reputation : if word got out that the patient he vouched for actually killed someone else after being released, the consequences for his career would be dire. And so he covers up the junkie’s death, and things start going from bad to worse.

(more…)