Join Barbie and her sisters Skipper, Stacie and Chelsea as they go on an adventure to a tropical island where Ken is doing a marine biology internship. After finding a family of gemstone dolphins being held captive by Marlo, the person Ken is interning with, they must join forces with a mysterious friend named Isla to save them before Marlo sends them away.

Nim Rusoe is a young girl who inhabits an isolated island with her scientist father and communicates, via e-mail, with the reclusive author of the novel she has been reading. Nim's existence mirrors that of her favorite literary character, Alex Rover, the world's greatest adventurer. But Alexandra, the author of the Rover books, leads a reclusive life in the big city. When Nim's father goes missing from the island, Nim gets Alexandra to come to her...