Some of these pictures and descriptions may give away plot details that you might not want to know before watching the film.
"A strangler... A swindler... A safecracker... Yet you'll love them!"
This is a black comedy set during Christmas that was directed by Michael Curtiz who also made Casablanca, Angels with Dirty Faces, and Mildred Pierce, made right after he made another Christmas movie - White Christmas. It's not quite the classic that those other movies are, but it has lots of subtle laughs. It's also the only holiday movie I know about where a venomous snake is a major character, and a likeable one, too. Unfortunately, we don't ever see the snake, only its cage, but the snake is mentioned frequently. Basically, this is yet another snake movie without a snake.
It's the late 19th century. Three convicts, played by Humphrey Bogart, Aldo Ray, and Peter Ustinov, escape from a prison on Devil's Island and go into a store in town to steal clothes and money. But when they meet the owner, his wife and their young daughter, they learn about the family's financial troubles with tyrannical Cousin Andre, (Basil Rathbone) and the daughter's romantic problems with Andre's son Paul, so they decide to intervene. But first they go steal wine, food, and a tree, and prepare a huge Christmas dinner. Andres and his son come late Christmas eve and the three men can immediately see they are both rude, obnoxious, and despicable men.
Bogart makes a fake Last Will giving half his money to the daughter and then they plan to kill Andre with a pet snake that Ray carries around in a wicker cage named "Adolphe." Before they can sick Adolphe on Andre, Bogart has second thoughts. He decides it would be bad for the family if Andre dropped dead in their home. But Andre then comes in and sees the cage. He demands to know what is in it, fearhing that they stole something. They tell him it's a snake but he doesn't believe it and takes the cage into a bedroom.
During a long comic delay, the three men, who obviously want Andre to open the cage and die, slowly discuss which one of them should "rush in and warn him" not to open the cage, but of course, by the time they decide and Bogart finally goes in, it's too late. They discover that the snake has escaped and they search all over the house for it but never find it, all the while making jokes about how since the nice little snake bit nasty Andre, the poor snake might be suffering.
Meanwhile, the son Paul lies about the Last Will and says that he will not marry the daughter and acts as obnoxiously as Andre did. The three guys consider killing Paul, but he goes into the bedroom to rifle through his dead father's pockets then comes out and says that he was bitten on the hand by a snake that he found in his father's pocket. The three guys rejoice about Paul's impending death, happy that they have also found Adolphe. Paul drops dead soon afterwards. At the very end, after Bogart declares that the three convicts are not angels, we see them walk away, and as they do we see a halo pop up over the first man's head, then the second, then the third, then after a delay, a fourth halo pops up over the snake's cage.