The Pickles family and friends decide to take a vacation. Their ship isn't very seaworthy, and end up stranded on an uncharted island. The kids figure the day is saved when they discover that famous explorer Sir Nigel Thornberry is also on the island with his family. After he gets a hit on the head by a coconut, Nigel's intelligence gets knocked out of commission. The Rugrats then turn to Nigel's daughter, Eliza, who not only knows the wilds, but can talk to animals, which comes as quite a surprise to Spike, the Pickles' family dog.