Mizuumi no himicu (E03)

A tip sends Dan and Furuhashi into the mountains to look for a crashed extraterrestrial object, where they pursue a strange girl. The chase eventually takes them to an alien ship. Dan sees through the girl's flirtatious responses, but before he can press her further, a trap knocks them all out. As Dan's consciousness fades, he sees an alien figure reach into his pocket and steal his Ultra Eye. (Prime Video)