The Suspicious Neighbor (怪しい隣人 Ayashii Rinjin) is the tenth episode of Ultraseven.
Akira, a young boy with a broken leg, spies peculiar goings on at his neighbors house. He tries to tell his mother, but she doesn't believe him. With recurring strange phenomena, the Ultra Guard get involved. Upon visiting the little boy, Dan vanishes; seemingly sucked into another dimension. In this otherworldly place, Dan meets Icarus, an alien with plans of planetary conquest. Occupying the Fourth Dimension, Dan is powerless -- he cannot change into Ultraseven, nor use his capsule monsters. Meanwhile, the Alien Icarus attacks the Earth in their enormous saucer.
- Dan Moroboshi/Ultraseven (モロボシ・ダン／ウルトラセブン（声） Moroboshi Dan/Urutorasebun): Kohji Moritsugu (森次 晃嗣 Moritsugu Kōji)
- Anne Yuri (友里アンヌ Yuri Annu): Yuriko Hishimi (ひし美 ゆり子 Hishimi Yuriko)
- Shigeru Furuhashi (フルハシ・シゲル隊員 Furuhashi Shigeru): Sandayū Dokumamushi (毒蝮 三太夫 Dokumamushi Sandayū)
- Kaoru Kiriyama (キリヤマ・カオル Kiriyama Kaoru)： Shoji Nakayama (中山昭二 Nakayama Shōji)
- Soga (ソガ Soga): Shinsuke Achiha (阿知波信介 Achiha Shinuske)
- Amagi (アマギ Amagi): Bin Furuya (古谷敏 Furuya Bin)
- Narrator (ナレーター Narētā): Hikaru Urano (浦野光 Urano Hikaru)
- Ultraseven (ウルトラセブン Urutorasebun): Koji Uenishi (上西弘次 Hirotsugu Uenishi)
- Ultraseven Volume 3 Features Episode 9-11, & 13.
- This episode was later featured in New Ultraman Retsuden episode 11 "The Suspicious Neighbor! Seven vs. Alien Icarus."