Phineas and Ferb: Just Passing Through/Candace's Big Day

In the special, it's Christmas Eve and an excited Phineas and Ferb are working to turn the city of Danville into a giant shimmering thank you card to Santa Claus. Meanwhile, Dr. Doofenshmirtz develops a Naughty-inator and suddenly, the Tri-state area is clouded in naughtiness and kids' letters to Santa are returned unanswered. Two of Santa's British elves arrive to investigate, but Phineas and Ferb must quickly devise a way to spread holiday cheer, all while Mom and Dad go to the airport to fetch Grandpa and Grandma Fletcher who've just arrived from England. Meanwhile, Candace tries, in a not so covert way, to figure out what's on Jeremy's Christmas wish list.