Believe It Or Else is a 1939 Merrie Melodies cartoon directed by Tex Avery. The short subject features Egghead.
The host tells the audience he has interesting facts to show them that he's collected on his many trips around the world, but Egghead walks across the stage with a sign that reads, "I don't believe it."
A man named Mr. Holstein Cudd has consumed 50 quarts of milk a day for the last two years. When asked how he feels, he responds with, "MOOOO" and continues to drink. Next is a Hindu snake-charmer that the host met while he was traveling last year. The snake plays on a flute and a man comes out of a basket and undulates like a snake. The next act is a man who builds ship models in bottles, but he is actually inside a bottle and building a ship outside of one. The next act is Mr. Adolphus Hambone, the world's loudest hog caller who can be heard from Arkansas to Walla-Walla Washington. His yells cause pigs to sing, "I hear you calling yoohoo," as they hear his voice. Next is a man who has not been out of his room for fifty years, but its an old man locked in a prison cell who says, "I'm a bad boy". At a California university, the narrator has found the human basketball. The man dribbles his round belly down the court and throws himself through the hoop. Next we have an optical illusion. The host is going to show the audience that the two squares on the screen them are not the same size. He asks the people in the audience to close their left eyes, and then their right eyes, in the process spotting that someone in the audience was peeking. He then shows them three triangles formed from nine matches. He tells them it is possible to make 37 triangles out of the three. He rearranges the matches faster and faster until all is a blur, then displays a jumbled mess and suggests that the audience should try it on their friends. Next the hosts says, "Atop Palomar mountain, California science takes a step forward with it's 200-inch telescope and brings you actual pictures of life on mars." There are actually spaceships flying around the planet mars, and a man named Buck Dodgers comes out saying, "Don't miss me in next Sunday's funny paper, boy it's a killer thriller," before getting back in and taking off. Egghead also lands on mars and still doesn't believe it, before taking off. The telescope then shifts to the moon, where the host hopes to prove to the audience that there is no life. But a trio on their way to The Major Bowes Amateur Hour asks if he knows the way to Cleveland. The narrator asks them to sing their number and they do, a slow barbershop song, "Sweet Genevieve". He tells them to hurry up and they sound like a sped-up recording. In Egypt there is a wishing well that will make your wishes come true. A man tells the wishing well, "I wish I had a million dollars," and the well replies, "So do I!" Egghead walks past holding a sign reading, "It's a fake." In the logging country of Tall-Timber, the announcer found Mr. Chopoffski, the world's fastest wood chopper. He quickly chops a tree and waits dramatically for it to fall, but it was only a stump in the first place. The narrator introduces Nathaniel Nevermiss, the country's most accurate knife-thrower. He throws his knives toward his sidekick off-screen, then appears shocked and asks the audience if there's a doctor in the house. For the first time on any screen will be shown the berth of a baby, a berth on a railcar. With the aid of a super-sensitive microphone the audience is actually going to hear the sounds of ordinary ants. An ant loudly shouts to its mate, "Hey Mabel!" Lastly, the narrator introduces Mr. Horace Buzzsaw who can saw a person in half. Egghead walks by, and proclaims that the stunt is done with mirrors, and still doesn't believe it. He is encouraged by the narrator to step inside the box and see it for himself. He does, and still doesn't believe it, until he sees his legs walking off, and he chases after them.