User blog comment:Anomymous Writes/Crossover with Phineas and Ferb/@comment-5188559-20130902135353

I think it's a great idea. They're both popular and imagine the ratings. The story: Phineas, Ferb, Candace and their parents find out about the Mystery Shack and want to visit. Phineas and Ferb invite Isabella, Buford and Baljeet to tag along. Major Monogram assigns Agent P to go to Gravity Falls where Doof is, figure what he's up to and stop him. Once the kids, Candace, Lawrence and Linda reach the Mystery Shack, they meet Dipper, Mabel, Stan, Soos and Wendy. The parents explore the Shack while the kids ask the Pines twins how its like in Gravity Falls and they show them how it is. Agent P arrives in Gravity Falls to find out that Doof is planning to create a Using the Abnormality-inator which he plans to use all the abnormality Gravity Falls has to take over the Tri-State Area. While the kids and Pines twins and exploring Gravity Falls, they encounter one of the abnormalities Gravity Falls has. They try to stop it by using an invention Phineas and Ferb created and Pines twins are impressed.