Behold! Ultra Horror Series - Vampire! The Bat Girl (見よ! ウルトラ怪奇シリーズ・吸血鬼! こうもり少女 Miyo! Urutora kaiki shirīzu kyūketsuki! Kōmori shōjo) is the 18th episode of Ultraman Leo. It is the second of the 5-episode story arc, Behold! Ultra Horror Series (見よ! ウルトラ怪奇シリーズ Miyo! Urutora kaiki shirīzu)
A horde of vampire bats is shot down, and Momoko finds a wounded girl in a field. Tooru suspects something of her.
The weather suddenly changes, and it seems as though there is a filter in the air above the city. MACCY 2 and MACCY 3 patrol, and a swarm of shadowy Showa-era effect rendered vampire bats arrive. They shoot them down, and the sky goes back to normal. One plane continues to patrol and the other reports to base.
Meanwhile, Momoko takes out Tooru and his sister on a picnic. They hear a wailing and find a girl passed out on the ground. She revives and says not to call anyone because she's being pursued by a bad man. Momoko takes her home, but Tooru doesn't believe the girl's story. He suspects she is a vampire bat. The next day, Momoko goes out and tells her to eat if she wants to get better.
She gets up and throws her food to the dog. She then spits on the bird to get it to "shut up". Meanwhile, at practice, Tooru tries to tell Gen of the girl but Momoko stops him. In a bit under two weeks, the girl is well, and sitting with Tooru's family during meals. That night, Tooru woke up but fell asleep before noticing the girl: she used a jewel on her chest to put him to sleep. She goes out into the night and begins sucking blood, while vampire rumours spread.
People begin to become vampires, and those suspected are brutally staked on-screen. Mac searches for the original vampire, as the only way to heal victims is to infuse them with her blood. Momoko begins to suspect the woman and asks her, right after she tastes the children. Batton, Tooru, and his sister drink Momoko's blood, creating yet another vampire.
Gen decides to check on Momoko. They all attack him, but he knocks them out. He chases after the vampire girl as she runs off into the night. Gen and a Nameless Mac Member Who Will Eventually Be Killed corner her, and she transforms into a giant. They are literally blown away, but Gen manages to transform.
Batton has the upper hand in the fight until Leo cuts off its wings. He then rips out its fangs. He conjures a syphon out of nowhere and extracts its blood before destroying it. The vampireized humans are turned back to normal. And Momoko doesn't change a bit.
- Ultraman Leo Volume 5 features episodes 17-20.