Beheeyem is a brown extraterrestrialPokémon with an oblong head that features depressions on both sides. It has black, symmetrical lines going down the front of its head. Under the rim of its head, there lay two green eyes with small black pupils. It has a lighter brown "collar" and four dots on its chest of the same color. Beheeyem's arms have three finger-like digits: one red, one green, and one yellow. It has a rim underneath its main body, under which are two small legs.
Beheeyem communicates by flashing its multi-colored fingers in patterns; these patterns have yet to be decoded. Beheeyem can manipulate the memories of its opponents, being able to erase or even rewrite them. Beheeyem is believed to be responsible for the mysterious disappearances of Dubwool whenever it visits a farm. It is sometimes found hovering over wheat fields.
In Capacia Island UFO!, multiple Beheeyem were searching for a koban that fell in Capacia Island when their flying saucer crashed there. They had hypnotized the town's population to help them in their search.
Pokémon Super Mystery Dungeon: Three Beheeyem first appeared when they attacked the player when they first appeared in the world. One of them was responsible for the memory loss the player suffered and were under the control of Dark Matter.
This Pokémon was unavailable prior to Generation V.
Beheeyem seems to be based on greys, one of the more popular kinds of alien. Judging from Elgyem's Pokédex entry, they may also be based on the Area 51alien conspiracy theories or the Roswell incident. Additionally, Beheeyem's design resembles a person wearing a hat and trench-coat and is likely based on stereotypical spies, shady figures, "Men in Black", or government agents in connection with alien sightings. The colored fingers on its hands resemble the colorful faces of the invaders in the 1953 War of the Worlds film; the aliens in the film had green, blue and red dots just like Beheeyem's Shiny coloration.
The flashing patterns of its fingers may have been inspired by the 1977 sci-fi film Close Encounters of the Third Kind, particularly the iconic scene where flashing color and sound patterns are used to communicate with the alien mothership. Its rock-like design may reference Japanese Dogū statues, which have often been confused for alien artifacts. Considering its species names, physical appearance, and powers, it may also be based on a brain.
Its connection with the disappearances of Dubwool and lingering over wheat fields are likely references to common alien behaviours in fiction - abduction of livestock and burning crop circles into farmland. Beheeyem might be based on alien plants from 1950s horror film called Invasion of the Body Snatchers.
Beheeyem may be a combination of behemoth and the abbreviation BEM (bug-eyed monster, a depiction of extraterrestrials as grotesque creatures with oversized eyes).
Ohbem may be a combination of 大 ō (large) and BEM (pronounced as a single word in Japanese).