"The Legend of the Dragon Tooth" is the fourth episode of American Dragon: Jake Long.
Haley is about to lose her first tooth, but since it is a dragon tooth, it holds mystical powers. The Tooth Fairy's assistant, Dr. Diente, has been biding his time until a dragon tooth came along. Seizing his opportunity, Diente captures the Tooth Fairy, steals her wand, and goes after Haley. However, upon reaching the Long house, Diente discovers that it is protected by a mystical shield, preventing him and his Tooth Minions from going inside. Diente waits outside to make his move.
Meanwhile, Jake wants to go to a concert of his favorite singer Shaniqua. However, as he is getting ready, his mother comes in and tells him that he can't go to the concert because he has to babysit Haley. But thanks to Spud and Trixie's arrival and assistance, Jake gets to attend the concert. Spud and Trixie take care of Haley for 20 minutes, and then Jake comes back and babysits Haley for another 20 minutes.
Eventually, when Jake's idol singer Shaniqua comes on TV, Trixie and Spud can no longer babysit Haley because they want to watch her live as well. Jake ultimately decides to take his sister along with them to the concert.
Meanwhile, the Tooth Fairy (after barely escaping being crushed by a car smasher) arrives at Grandpa Lao Shi and Fu Dog's door and explains Diente's plan, and Fu and Grandpa realize that Haley's in danger.
While Jake and his friends take Haley to the concert, Dr. Diente makes his move. Diente has his Tooth Minions corner Jake and Haley and while Jake fights the Tooth Minions, the evil dentist kidnaps Haley and takes her to the Tooth Fairy's lair. Jake, Grandpa and the Tooth Fairy arrive and in the ensuing battle, Haley's tooth flies out and lands in Diente's hand. Diente takes it and wraps his hand around it and places his hand into a pot of soil, causing the tooth's powers to activate and turn Diente into a giant white-furred monster.
Diente goes on a rampage throughout New York and starts to steal the money the Tooth Fairy gave to children. Luckily, Jake is able to stop Diente with his dragon powers by taking a billboard-sized TV and smashing it on top of him, destroying him for good and leaving only his shattered glasses on the street.
Jake picks up Haley's tooth from Diente's remains and they fly back home. Jake and Haley are sitting in the dismantled living room (the aftermath of Trixie and Spud's failed attempts to pull out Haley's tooth) when Susan and Jonathan arrive to see the huge mess. However, Haley quickly steps in and takes the blame for it, claiming that Jake tried to stop her from destroying the living room. However, Susan and Jonathan's anger quickly turns to excitement as they notice Haley's missing tooth and rush to get the camera.
That night, as Jake tucks Haley in bed and places the tooth under her pillow, she thanks Jake for ditching the concert to save her. Jake replies that he's sure he didn't miss much. The scene cuts to Trixie and Spud having a blast while riding in Shaniqua's limo as the episode ends.
- The episode's title is a reference to the popular video game The Legend Of Zelda.
- Haley eating a lollipop with a loose tooth is a reference to the Mr. Bean episode "Toothache", in which Mr. Bean eats popcorn with a loose tooth.
- Dr. Diente's transformation into a monster tooth is a reference to HIM transforming into a monster in The Powerpuff Girls episode "Tough Love".