Simon feels unappreciated and stows away on a cargo ship; Dave, the Chipmunks and the Chipettes go to Washington D.C. to lobby the president to save bald eagles.
Alvin recruits Eleanor to play soccer; Dave's piano is filled with pudding and thrown down the stairs, and each chipmunk has a different story as to how it happened.
After a concert, the Chippettes meet up with Olivia, an old friend from the orphanage in Australia where they grew up. They explain how they escaped from it and its evil headmistress and came to be singing sensations.
Simon goes on a game show, but when he wins, he catches the flu and his brothers must pose as him for future appearances; Alvin sells Dave's motor home to buy a gold claim.