The Flower Where the Devil Dwells (E31)

A woman falls ill after finding a strange silver petal. The victim, Kaori, assaults a nurse and Amagi before being brought down. The Ultra Guard realizes that Kaori is looking for blood because the silver petal contained a space bacterium known as Dallie. In order to save her, Dan transforms into Ultraseven and shrinks himself to a microscopic size to fly inside the woman and pursue Dallie. (Prime Video)