Humanity invented a medical device capable of completely curing cancer at its most fundamental level, then developed a ray gun. Twenty years later, they discovered how to travel through time and space. One month after this discovery, Earth faced a monster crisis. The protagonist, Aini, was there at the time. His father, Aiyan, invented the ray gun. During a mission to Mars, Aiyan and his wife encountered a monster called Mohela. They were attacked and killed by the monster. After learning the news, Aini grieved for a month. Then monsters suddenly appeared on Earth. Aini saw one wreaking havoc across the city, so he used a car to lure it away. Suddenly, the monster hit him with a beam of light. Just then, an alien called Ultraman Kaidi rescued him, and together they fought the monster.
