As Phineas and his friends travel on vacation to Gravity Falls, they meet the Mystery Twins and embark on a dangerous adventure in order to seize the day. Meanwhile, Doofenshmirtz gets into all kinds of trouble in this strange new town.
Crossover - Phineas and Ferb & Gravity Falls - Rated: K+ - English - Humor/Adventure - Chapters: 26 - Words: 19,091 - Reviews: 134 - Favs: 69 - Follows: 38 - Updated: 4/1/2016 - Published: 9/13/2015 - Phineas, Dr. Doofenshmirtz, Dipper P., Grunkle Stan - Complete