Mr. Happy's Plot: Mr. Happy gets his eyes exam, though with Mr. Stubborn as his eye doctor, he gets the wrong results.
Little Miss Helpful's Plot: Miss Helpful advertises on the fashionable eye wear.
Little Miss Whoops's Plot: Miss Whoops loses her glasses as a plane waiter and has a hard time telling who's who, even when temporarily having Mr. Nervous' glasses. She soon makes the ride terrifying for the other Mr. men and Little Misses.
Trivia
The three glasses-wearing characters do a rap song called "Four Eyes are Better Than One". (Not in UK)