Pelle and Pingo agree to help Rasmus build a boat to Old Salt.

Rasmus and his friends go exploring aboard the Mary. Suddenly, they find themselves atop a mysterious island.

Rasmus, Pingo and Pelle are rolling barrels along the coast, as they discover that the good ship Mary hadn’t been properly tied up and has now disappeared. Old Salt explains that the current can quickly pull boats out to sea. What to do?

On board The Mary, Rasmus peers through a telescope at a passing island and discovers a family of kangaroos: Peter and Betty with their little one. Peter proudly shows Rasmus the car he’s building.

Sailing with the good ship Mary, Pingo discovers a bottle full of confetti and a promo flyer from Pete Peterson’s Party Island. This makes him come up with the idea of a surprise party for Rasmus.

The friends aboard the good ship Mary come to a small, peaceful island covered in sand dunes. Suddenly, Pingo hears a cracking sound. The noise is coming from an egg and he watches a turtle hatch from it.