Phineas And Ferb: Season 3, Episode 31

3 - 31:

When Mom is out of Doonkelberries for her famous Doonkelberry pie, the boys set out to find some for her. Meanwhile, Perry and Dr. Doofenshmirtz find themselves across the ocean as Doofenshmirtz returns home to renew his Druelselsteinian driver's license. Back in Danville, Candace is convinced she has discovered the answer to her busting problem.