Ultraseven Episode 3

An unidentified object has landed somewhere near the Kiso Mountains. Dan and Furuhashi are sent to find any wreckage, or signs of life. They find a young girl swimming in Lake Azuma as well as a spaceship nearby. Both men go aboard the craft where they find a girl that looks exactly like the one they saw swimming in the lake. The two men are temporarily knocked unconscious by gas emitting from the walls of the ship. When Dan comes to, he realizes the Ultra Eye is missing. Without it, he can't turn into Ultraseven. Not long after, a giant monster named Eleking emerges from Lake Azuma. Till he can locate the Ultra Eye, Dan uses one of his capsule monsters to send Miclas to battle the amphibious Eleking, a beast under the control of two insectoid twin aliens know as Alien Pitts posing as little girls with plans to wipe out all of mankind. (Source: ultra.fandom)