insomnia (2002)

los angeles detectives will and hap travel to northern alaska, where the sun never sets, to help the police of a small country solve the difficult case of a 17-year-old murdered woman. the character of experienced navigators of every form of violence is thus opposed to the simplicity of mind of local agents. will's attention focuses on the ambiguous writer walter finch and to nail him down he doesn't look thin, even going so far as to modify evidence. but the suspect does not let himself be taken aback and shows that he is very good at the game so that a real brain challenge takes place between the two, which seems to put the policeman's psychic balance in difficulty.