Thomas Edison exists as a luminous spirit composed of sentient substance within the Tathagata Realm, the eighth dimension of Heaven. He contacts protagonist Ryuta Hoshikawa through an unnamed Inca shaman, telepathically transmitting schematics for his unfinished "spirit phone" directly into Ryuta's mind.

This portrayal presents him as a selfless visionary dedicated to humanity's advancement through spiritual technology, omitting historical controversies. It further elevates his legacy by revealing Johannes Gutenberg and Cai Lun—inventors of the printing press and paper—as his past lives, forming a lineage of enlightenment-driven innovation.

Within the Spirit World's hierarchy, Edison serves as a celestial guide. He provides Ryuta and Yuko Natsuse access to an interdimensional elevator enabling travel to the Cosmic Realm (ninth dimension) or descent into Hell, facilitating their journey to confront demonic entities threatening trapped souls. Residing in the Tathagata Realm, he collaborates with Albert Einstein to oversee scientific progress across dimensions, focusing on their shared mission to uplift human consciousness.

His role expands during the climax in Hell's Demonic Realm, where he remotely transmits blueprints for a giant Hermes mecha to assist Ryuta in combat against Hisler's demonic elephant, Bihimoss. This action bridges scientific ingenuity with spiritual warfare against corrupting ideologies.

Ultimately, Edison embodies the Happy Science doctrine, framing inventors as enlightened beings whose innovations serve a divine plan. His revelation of Ryuta's "Chosen One" status to guide humanity toward the Eternal Buddha positions him as a narrative conduit for the film's religious teachings.