Proper Japanese Title: 鉄腕バーディー (Tetsuwan Bādī)
Federation Space Police Agent Birdy Cephon Altera is in pursuit of a gang of interplanetary criminals who land on Earth.
While chasing one, he grabs unsuspecting high school student Tsutomu Senkawa and tosses him at Birdy from while reminding hidden, thinking she is being attacked she kills him with a blast of electricity.
On returning to her ship to give her report and the capture of the criminal her chief is furious about the death of Tsutomu and orders that Birdy save his life anyway she can.
The only way this can be done it turns out is for her to merge with his body, bring him back to life and letting the sophisticated technology that is part of her repair the damage, unfortunately for Birdy the process to fully restore Tsutomu is a long one, not willing to remain hidden and inactive, Birdy from time to time takes over his body and turns back into herself to take down other intergalactic criminals who have take an interest in Earth, at first Tsutomu only experiences this as strange dreams, and questions from his family and friends about why he keeps disappearing.
Eventually however he becomes aware of what is happening to his body and experiences Birdy’s adventures though her senses.
They also become able to communicate with each other when either Tsutomu or Birdy are in command of their shared body.
So Tsutomu is stuck sometimes having his body turn into an impulsive female space police agent, while trying to keep his family and friends from finding out about Birdy.
In the meantime, Birdy continues her investigations. Together, they take on a secretive group of evil aliens planning to turn the whole human race into monsters under their command.
Birdy the Mighty has appeared in a number of different version and with a surprising number of different publishers both in Japan and in translations around the world.
It was also turned into an Anime series.