Mickey Mouse is walking down the street when he sees a cold, homeless orphan in the alley. When Mickey takes him to the local orphanage, he finds that it is all full, so he decides to start a fund to raise money for the orphanage. When walking along to collect some money, Mickey gets blown away by the wind, causing the sandwich board he's carrying to turn into a makeshift flyer and he inadvertently wins a flyer contest, giving him $50 to start the fund. Mickey then tries various ways to raise money for the fund, such as selling Horace's photo and washing dogs, until Mickey saves the life of the wealthy J. Clipper Bond, who in return gives him one dollar for every one he makes, thus doubling the raised money.
When Mickey brings the news to the orphanage, he learns that the orphans need a hefty $1500, leaving Mickey to scramble for an idea to raise a lot of money until he and Minnie get covered in soot from a car's exhaust pipe and they get the idea to put on a production of Uncle Tom's Cabin, with Mickey as Uncle Tom and Topsy, Minnie as Eva, Horace as Simon Legree, Clarabelle as Eliza and Pluto as a bloodhound. Mr. Bond lets the gang rent the opera house for free and despite a few mishaps, the play performs well to a sold-out house. The next week, the gang holds a party to celebrate them reaching their $1500 goal, and it is there that Horace and Clarabelle announce that they have gotten engaged. When Horace goes back to bring out the money, there is a loud racket from the other side of the door and Minnie discovers that both Horace and the money are gone.
Mickey goes to the authorities for help, but they assume that Horace stole the money and start a search to find him. Horace is found and arrested. Mickey sets out to prove his friend's innocence and discovers that the robbers were his old enemies Sylvester Shyster and Peg-Leg Pete. Just after his discovery, the two scoundrels knock Mickey out and make away with the money, and worse, the police are told that Mickey has disappeared, making them assume that Mickey was an accomplice in the robbery. When Mickey regains consciousness, Mickey runs after a train that the villains have gotten away on and Mickey crashes through to where Shyster and Pete are hiding on a hand-rail car. After a lengthy fight, the villains escape and Mickey finds himself shipped on the train to the far North. There, Mickey finds a wanted poster of himself, so he decides to put on a trapper's outfit as a disguise and he ends up getting a job playing the piano in a saloon.
Shyster and Pete stop by at the saloon with the money. Mickey spots them and tries to fight them, causing a bar-wide brawl to break out and the Mounted Police to arrive on the scene. The bartender puts Mickey in a barrel to hand him over to the Mounties for the $500 reward, but Mickey gets away, as the bottom of the barrel wasn't nailed down, and escapes from the saloon, but he accidentally rings on a police bell, and he gets thrown into the jail. Meanwhile, Horace is tried for allegedly robbing the orphanage, where he will be put to death if he's found guilty. Mickey manages to escape by awakening a guard bear so he can run with his prison bars in tow, and Mickey rides on the bear to catch Shyster and Pete. Mickey ends up getting ambushed by the two and he gets tied to a tree, with the ropes rigged to that Mickey will get shot if he moves, but the bear arrives and rescues him. Meanwhile, Horace's trial goes on with the district attorney determined to find him guilty. When Horace gives him a punch in the eye for calling Mickey a scoundrel, he plots to pin every unsolved crime in the past ten years on Horace.
Soon, Mickey is trapped in a blizzard and finds shelter in a cabin, where he finds the orphanage money hidden in a stove. But, Shyster and Pete show up and a fight between good and evil breaks out. This time, Mickey wins the battle, ties the villains up and rushes to get to Horace's trial fast on the villains' sled, especially since some hoodlums are planning to lynch him when his verdict is announced, Mickey soon finds an abandoned airplane, but he ends up crashing it. Mickey soon gets the attention of a mail plane and (with all three of them covered in stamps) they fly for home in a race against time. Mickey them jumps out the plane with his captors and into the courtroom just as Horace is declared guilty and he is about to be hanged. Mickey produces the money and the robbers and he and Horace are declared innocent. All is well again for our heroes, but Mickey them gets a letter that will lead him into his next adventure.