Just as Azul starts to take the lead, the sneaky fox Swiper appears and swipes five blue square pieces of the train track. Dora and the viewer must find the missing squares and put them back so Azul can continue the race.
Dora and Boots decide to help Azul enter the . The first train to reach the Big Yellow Station will win a brand-new, shiny whistle. Their journey follows three main steps: Just as Azul starts to take the lead,
The tunnel is pitch black. Since Azul has no whistle to warn other trains, Dora uses a flashlight from her Backpack to see, and they all whistle together to let other trains know they are coming. The first train to reach the Big Yellow
In the episode " Choo-Choo! ", Dora and her best friend Boots visit the train station where they meet , a little blue train. Azul is sad because he is the only train without a whistle, and the bigger trains, Big Red and Big Green, often make fun of him for it. In the episode " Choo-Choo