Betelgeuse is the main protagonist of the 1988 live-action film and animated cartoon of the same name. He is the main antagonist of the film, but has a more heroic role in the cartoon.
He is voiced by Stephen Ouimette in the cartoon.
Betelgeuse's pranks on many seem to cause them great embarrassment or damage, but for Lydia, his pranks are only done to tease her, not to cause harm, which shows he cares for her. In fact, Lydia seems to be the only person who has any control over Betelgeuse. He even said in one episode he would do anything for her, and she, in turn, reciprocates his feelings. Betelgeuse is also constantly coming up with get-rich-quick con schemes to get money, as he dreads having to get a job, and in later episodes (particularly in the second half of the fourth season), Betelgeuse's greediness becomes so intense that he starts to overlook his friends and family, and even when Lydia openly scolds him, Betelgeuse shows unbelievable reluctance or unwillingness to give up of his schemes. His favourite foods are insects of various types, especially beetles, and worms. Betelgeuse also loves causing mayhem in the Neitherworld and being filthy, and this last makes Betelgeuse have a pathological and psychotic hatred of baths (at one point, when Poopsie once waters him (Betelgeuse) with a hose, Betelgeuse went berserk with fury and was nearly going to eat Poopsie). Despite this cynical and childish attitude, Betelgeuse proves to be a profound and insightful person, frequently reciting quotes of philosophical and humanitarian importance (but of course, Betelgeuse rarely follows his own lessons and lectures). The things he hates include Sandworms, cleanliness, and anything "cute". He expresses his likes and dislikes via variations on a single catchphrase, as in "Nerd humour you know I love it!" or "Sandworms you know I hate 'em!" Betelgeuse's origins are rather fuzzy. On one hand, he frequently claims to be dead, a ghost, (having died centuries before—though his references are often hundreds of years apart), which implies a prior life in the "real world".
He is the oldest son of Nat and Bea Geuse (who nag him to get a job and to keep clean, and who always address his as "Junior"), and he has a "disgustingly cheerful" younger brother, called Donald "Donny" Geuse (who, whether he realizes it or not, gets on his older brother's nerves).
At times, he must pause to think of exactly how to use his powers to escape a precarious situation unscathed. Due to what is later described in the series as his "juice" (his inborn source of magic), whenever Betelgeuse utters aloud a figure of speech, he or his surroundings change to act on the pun (for example, if he says he is tired, he will transform into a tire; if he says he is flat broke, he transforms into a flat disc that falls to the ground and shatters; on one occasion, in reference to his own power, he declares "This literal translation stuff slays me!" and giant letters reading "Literal Translation Stuff" then fall from the sky to crush him). Almost all of his transformations maintain the black-and-white striped pattern he wears on his suit, although sometimes the stripes are coloured depending on the transformation. Though many Neitherworld denizens have some magic, it is Betelgeuse's greatly superior power (no real cause for it is ever given) that affords him the title—albeit mostly self-asserted—of "The Ghost With The Most" (another line borrowed from the movie); in fact, on multiple occasions Betelgeuse was able to effortlessly subdue a number of supernatural beings, and his dis-corporeal, self-sentient brain once claims that Betelgeuse's power is more than enough to conquer the whole Neitherworld. Because of that power, almost everyone in the Neitherworld is fair game for his pranks, though no more so than he himself, since he is not immune to careless use of his power; for example, he was once tricked by his enemies into saying "I'm coming apart at the seams!" which caused him to break into several pieces, which his enemies then stole and scattered to different places in the Neitherworld rendering him helpless (as Betelgeuse can only use his powers when all of his body parts are together). Also, if all of his body parts are not reassembled by sundown, he will "melt away". Thankfully, with Lydia's help, he soon gathered all of his body parts and was able to "pull himself together". Sometimes Betelgeuse will mix up one of his transformations, due to homophone-based confusion (when Lydia told him to turn into a stake to fight off Count Me-In, he turned into a flank steak). At times, various of his body parts (including his feet and his entire torso) manifested minds of their own, independent of Betelgeuse's control, with his brain and even his entire skeletal system having abandoning him once. Betelgeuse's main pastime is pulling various pranks on the other denizens of the Neitherworld such as Jacques, Ginger, The Monster Across the Street, Poopsie, the Mayor and in the Living World it is Lydia's rival Claire Brewster.
Yet some episodes show his parents residing in the Neitherworld, and it is apparently there that he was born to and raised by them: there are, for example, photos of him in the Neitherworld as a baby—-showing him with his stock ghostly complexion and bizarre snake-like tongue—-and tales of his youth already manifesting his trademark personality. One possible explanation may relate to his saying something about his parents "making him feel like a kid again" and being unsure how to fix it without his growing up all over again; another is that continuity was not of key importance in the series. He have in fact have been 'reborn' in the Neitherworld after his death in the real world. More likely, the creators probably changed it to avoid scaring off viewers; (in later airings, he is shown in new animation in the opening leaving his grave as a corpse; the original opening for the first three seasons featured him producing stripes on his clothes), or the writers simply were not keeping track of plot details. A number of times, Betelgeuse interacted with Lydia's parents in the "real world" of Peaceful Pines, always under the name of "Mr. Beetleman", and in a couple of instances, he performed a gender change on himself to become a teenage girl about Lydia's age at Lydia's school as "Mr. Beetleman's" younger female relative "Betty Juice", along with once or twice appearing as the male gender "Cousin BJ" claiming to be on Delia's side of the family. In "Out of My Mind" it is revealed that Betelgeuse loves to pull pranks with spaghetti. In one fourth-season episode ("Substitute Creature"), he appeared at Lydia's school as visiting teacher "Professor Beetleberg".
- Betelgeuse was named after the star Betelgeuse. Betelgeuse, (often addressed as Beej or BJ by Lydia for simplicity's sake, and because the results of his name being said aloud three times), is able to change shape, transform and conjure objects, teleport, and perform other feats of magic, although his powers can be reduced by various circumstances, such as encounters with Sandworms (despite the fact that he has enough power to subdue or repel them with ease) or when his head becomes separated from his body.