As described in the book, Brent Green first reveals himself to Middletown resident Sammy Jacobs, who initially believes Green to be a ghost. However, in the twist ending, it's revealed that Green is actually a human boy who was somehow made invisible by his mother, so he would survive in a world now inhabited by inhuman creatures (including Sammy and his family).
In the book, it's hinted that the story takes place on Earth, so it's unclear how these beings came to be prominence — or how humans became endangered. The television episode explains that Sammy's species invaded Earth and sent the humans away to space colonies.
Brent Green appeared in the television adaption of My Best Friend Is Invisible, portrayed by Darcy Weir. At the end of the episode, Sammy and his parents surround Brent menacingly, presumably with the intent of killing him.
Brent Green appears in the 2015 Goosebumps film voiced by Jack Black, but referred to and credited as the Invisible Boy. He suddenly appears on the windshield to R.L. Stine's car leaving noticeable hand prints. He climbs around the car and hits Champ in the face. Stine removes him by accelerating the car really fast then comes to an immediate stop flinging him from the car. He replies by shouting "Not cool!".
At the end of the film, he reveals to Stine that he somehow evaded getting captured by beginning a story titled The Invisible Boy's Revenge on Stine's typewriter and leaves hand prints on the trophy case as he tells Stine, "You forgot about me!" Stine screams in horror as Brent's hand print appears on the cabinet glass while Brent maniacally laughs. The image is then turned into a book cover with the tagline "Invisible but deadly."
Some see the Invisible Boy not getting sucked up by the book as a plot hole, due to Zach Cooper writing "all the monsters go back into the book." His ability to escape entrapment is never fully explained.
His final fate is unknown. He is presumed still at large or captured offscreen before Goosebumps 2: Haunted Halloween.
- "NOT COOL!"- Goosebumps (film)
- "You forgot about me!"- Goosebumps (film)