Psychic Wars

is a 1991 Japanese OVA anime film created by Toei Animation based on a novel by Yasuaki Kadota.

Plot
An old psychic woman enters a hospital in Osaka with a large cancer growth that is killing her. This sets off a chain of events that will open up surgeon Dr. Ukyo Rettsu to the knowledge of the supernatural and other realms. Dr. Rettsu discovers that the cancer is actually a demonic messenger, heralding that a prophesied invasion of the mortal realm is coming soon. The creature tells the surgeon that he is, in fact, the "Demon of The Sky" prophesied to halt the demonic invasion. Although the old woman dies, her glowing spirit imbues Dr. Rettsu with powers including superhuman toughness, strength and speed. In order to halt the demonic invasion, Dr. Rettsu must use his powers to go through a portal and travel back five millennia into history to destroy their ancient civilization in the past.