A (1998 Japanese film) (1998)
A is a 1998 Japanese documentary film about the Aum Shinrikyo cult following the arrest of its leaders for instigating the sarin gas attack on the Tokyo subway in 1995. The film focuses on a young spokesman for the cult Hiroshi Araki, a troubled 28 year-old who had severed all family ties and rejected all forms of materialism before joining the sect.
More at Wikipedia.