The Robinson family receives a letter from an old friend urging them to relocate to Australia.

While Becca looks forward to a new life in Australia, her older brother Fritz worries about the effect the move will have on his career options and considers remaining in Switzerland.

The Robinsons take a riverboat on the Rhine, where a con artist tricks Becca.

The Robinsons embark from an English port on their journey to Australia; Jack causes trouble while aboard; Dr. Robinson helps a pregnant passenger.

A fellow passenger named Emily worries her family will need to disembark prematurely due to a tiff.

A storm bombards the ship in the middle of Christmas celebrations, forcing an evacuation; the Robinsons stay behind to search for a missing Fritz.