The Greatest Show on Earth Trailer (1952)

Brad (Heston) is the no-nonsense general manager of what was at the time the world's largest performing troupe. He is confronted with troubles in his past. On one hand, home-office administrators plan to cut the season short, rather than risk losing thousands in the shaky post-WWII economy. He bargains with them to keep the circus on the road as long as they are making a profit, thus keeping 1400 people working. On the other hand, two of his acts, his girlfriend Holly (Hutton) and The Great Sebastian (Wilde), engage in a fierce aerial duel to show which act is the best. Finally, a crooked sideshow promoter and his henchman are running their own schemes, and Brad has to fire them despite their threats.

Another problem — unbeknownst to Brad — is the mysterious Buttons the Clown (Stewart), who is never seen without his clown paint. Early in the film, he meets a woman who tells him that an unnamed "they" are asking questions. We discover that she is Buttons' mother, and that they see each other only once a year. Hints about his former life come as he gives first aid to performers and wraps bandages around a trapeze in an expert manner. Holly later finds a newspaper article about a doctor who had "mercy killed" his wife.

The competition between Holly and Sebastian develops into a romance triangle, with both Sebastian and Brad vying for Holly, as the aerialists' acts become increasingly daring and dangerous. Sebastian meanwhile ignores his former girlfriend Angel (Grahame), who performs in the elephant act. The duel ends when Sebastian falls, after having cut his safety net away. He returns to the circus, but is unable to resume his act due to debilitating injuries. A guilt-ridden Holly professes her love for her former rival over the cold, unfeeling Brad, and a dejected Brad and Angel pair up.

When Sebastian makes his fall, Buttons tends to his injuries. When a doctor expresses admiration for the way he dealt with them, the clown explains, a little nervously, that he used to be a pharmacist's mate.

As they are about to leave one town, a detective intercepts Brad, asking if the circus doctor looked like a photograph of Stewart (without makeup). He boards the train to continue his investigation. Brad mentions this to Buttons, who tells him that Sebastian has feeling in his injured hand — a sign that his disability is not permanent. Brad makes the connection between Buttons and the fugitive doctor and comments that the police will be taking fingerprints.

The joy of Sebastian's potential recovery is smashed in the massive collision of the circus' two trains, set up by the crooked promoter and Angel's rejected suitor Klaus, the elephant trainer. Buttons, who had been about to flee, returns after a plea by Holly and saves the critically injured Brad's life (including a transfusion from Sebastian) despite knowing that the detective is watching, leading to his arrest. Holly realizes that she is actually in love with Brad, and, acting similarly to him, she takes over command, mounts a circus parade through the town nearest the crash and stages a show by the crash site, allowing the circus to avoid bankruptcy despite the crash.