Underground, Go! Go! Go! (E17)

After a cave-in traps a miner, the UG comes to help rescue the "Miracle Man." This jogs Dan's memory of when he "met" Jiro and witnessed him cutting his own rope to save his friend from falling with him in the past. Convinced of humanity's potential for kindness and self-sacrifice, the being that would be known as Ultraseven saved the man, taking on his form to experience a human life. (Prime Video)