Šinrjaku suru šišatači (E33)

A submarine convoy is travelling across the ocean with top-secret documents for TDF and someone is trying to get at it. The Ultra Guard is dealing with corpse-like invaders. Dan pursues a figure, determining that the corpses are being used as mediums for telekinetic shadows. He transforms into Ultraseven to fight them off, but they manage to shrink him until he can be captured in a glass cup. (Prime Video)