The Thief of Bagdad

The Thief of Bagdad is a 1940 movie, starring Sabu, John Justin, Conrad Veidt, and June Duprez. It borrows heavily from stories of the Arabian Nights. (There have been several movies using the name, including a 1924 silent film starring Douglas Fairbanks, Sr., but this article is about the first remake.)

Ahmad is the king of Bagdad. His vizier, the wily Jaffar, has kept him isolated in his castle his whole life. One day, Ahmad decides to go out into the city disguised as a peasant, so he can learn more about his people. Jaffar, sensing a chance to seize power, sends guards after the king; Ahmad has just enough time to hear a prophecy about a boy saving his city before Jaffar's guards capture him and throw him into the dungeons. He is sentenced to death in the morning, but luckily for Ahmad, he's trapped in jail with Abu, a young thief who has Bagdad—and the dungeon keys—in his pocket.

Abu and Ahmad embark on an amazing journey involving ancient prophecies, captured princesses, mechanical horses, magic spells that turn seeing men blind and thieves into dogs, assassinations, giant spiders, ship wrecks, flying carpets, and an absolutely enormous genie who will grant three wishes to anyone clever enough to survive him.

The Thief of Bagdad was very popular in its day, partly due the charm of child actor Sabu. It had a lasting influence on Hollywood; many of the tropes the Arabian Nights made were actually codified by this movie. It's also the first film to use Chroma Key.

Tropes used in The Thief of Bagdad include:

Always Accurate Attack
Animorphism: Abu is transformed into a dog.
Arabian Nights: It borrows heavily from the source. For example, when Abu frees the genie, it's initially angry at being held captive and wants to kill his rescuer, but is tricked back into the bottle and finally agrees to grant Abu three wishes. This is taken directly from the story, "The Fisherman and the Genie."
Arabian Nights Days: Trope Codifier for a lot of them.
Be Careful What You Wish For: Abu accidentally wishes Ahmad back to Bagdad after they fight, using up his last wish.
Big Eater: Abu.
Big Damn Heroes: Abu..
Catapult to Glory
Chase Scene: There's an energetic foot-chase early in the movie, wherein Sabu does all his own stunts. Incidentally, he was sixteen at the time.
Cool Horse: Jaffar's mechanical flying horse. Some assembly required.
- Mechanical Horse
Cool Toy: the Sultan of Basra collects mechanical toys, which makes it easy for Jaffar to bribe him with the above-mentioned horse.
Crystal Ball: The All-Seeing Eye Abu steals from a temple.
Deadpan Snarker: Quite a few.

Merchant: "Allah be with you. [beat] But I doubt it."

Earn Your Happy Ending
Everything's Better with Princesses: The Princess. She doesn't even have a name.
Evil Chancellor: Jaffar
Evil Sorcerer: Jaffar, again.
Evil-Detecting Dog: Taken from an Arabian Nights story where a dog that's really a person in dog form functions this way, Abu as a dog can identify bad coinage.
Evil Laughter: The Genie. Hammy, but still evil.
Death by Sex: This is the subtext in the sultan of Basra's murder.
Genie in a Bottle
Giant Spider: Abu fights one while climbing a web to gets to the All-Seeing Eye.
Give Me a Sword: Ahmad wants a chance to duel Jaffar. Jaffar declines and promptly blinds him.
Heroic Lineage: Ahmad is the grandson of Haroun al-Raschid. Possibly parodied with Abu:

Abu: "I'm Abu the Thief. Son of Abu the Thief. Grandson of Abu the Thief."

How We Got Here: the first act is told in flashback.
Humans Are the Real Monsters: Jaffar tries to convince Prince Ahmed that humans are evil, and makes a good case for it himself:

"Men are evil, hatred in their eyes, lies on their lips, betrayal in their hearts. You will learn one day, great king, that there are three things that men respect; the lash that descends, the yoke that breaks and the sword that slays. By the power and terror of these you may conquer the Earth."

- Later, the Genie has his say on the subject, after Abu's third wish goes awry (though this is more Humans Are Flawed):

"You're a clever little man little master of the universe, but mortals are weak and frail. If their stomach speaks, they forget their brain. If their brain speaks, they forget their heart. And if their heart speaks, they forget everything."

Hypnotize the Princess: Jaffar erases the princess' memories of Ahmad, hoping she'll start loving him. Slightly subverted in that he previously refused to use his powers to make her fall in love with him directly.
Hypercompetent Sidekick / Puss in Boots: Abu to Ahmad, who is pretty much a Fish Out of Water.
King Incognito: Ahmad.
Large Ham: Genie.
Love At First Sight
Love Potion: Inverted. The Blue Flower of Forgetfulness is intended to make the Princess forget about Ahmad.
Loveable Rogue: Abu
Magic Carpet: How Abu makes his grand entrance and grand exit.
McGuffin: This movie has everything, including one of these. The genie takes Abu to a temple where he has to steal a jewel to find Ahmad. The genie can't get it for him because... that wouldn't be fun enough.
The Mountains of Illinois
Musicalis Interruptus: briefly, when dog-Abu is caught by the executioner.
Prophecy Twist: The prophecy at the start of the movie says "a tyrant shall be overthrown by the lowest of the low, who appears on a cloud"; Ahmad and the peasants believe it's about him, but it's about a slightly different tyrant.
Raven Hair, Ivory Skin: The Princess.
Reverse Psychology: Used by Abu to entrap the genie.
Robot Girl: The sultan of Basra dies at her mechanical hands.
Scarpia Ultimatum: Jaffar reveals that the only way to restore Ahmad's eyesight is for the princess to embrace him; she does.
Sealed Evil in a Can: The genie, borrowing from the 1001 Arabian Nights tale "The Fisherman and the Genie."
Shout-Out: It is the subject of a lot of them; Aladdin's Abu is a monkey version of Sabu's character, and Jaffar is Conrad Veidt.
- The Aladdin series also features the Blue Rose of Forgetfulness in one episode. Not to mention that the Sultan of Agrabah basically is the Sultan of Basra, as is the King in The Thief and the Cobbler.
- Abu mentions Sinbad the Sailor was willing to give them berths on his ship...
Street Urchin: Abu at the start of the movie
Three Wishes: The genie grants Abu these.
Trope Codifier: For several "Arabian Nights" tropes, including Grand Vizier Jafar.
True Love's Kiss: Jaffar tries to exploit this by wiping the Princess' memory and then kissing her.
Visual Effects of Awesome: A lot of the special effects are astonishingly good for a film made in 1940. Extensive use is made of back-projection in particular.
The White Prince: Ahmad.