It's the summer solstice, so Phineas, Ferb, and their friends decide to travel around the world in one day in an effort to create the "biggest, longest, funnest summer day of all time". But not everyone believes they can actually achieve what they have set out to do, especially Buford. Candace tags along because Jeremy is on a trip to Paris, and she fears that there he may meet other girls. Also, Isabella finds her affections for Phineas sorely tested when his steadfast focus on achieving his goal puts pressure on her. Meanwhile, Dr. Doofenshmirtz takes a father trip to Tokyo, Japan with Vanessa, but sets out with Perry and Major Monogram to find her when she joins Phineas, Ferb and the others.

《探险时光》即《探险活宝》（Adventure Time，原始标题为Adventure Time with Finn and Jake）是一部美国电视系列动画，原创为潘得顿·沃德，在美国的分级为TV-PG。由卡通频道委托弗雷德瑞特工作室制播。故事追随人类芬·莫顿（Finn Morton the Human，台译：阿宝）和一只拥有任意改变形状及伸缩的魔力，是他最好的朋友同时也是养兄弟的狗儿杰克（Jakethe Dog，台译：老皮）展开的探险旅程，他们生活在后末日的哇赛秘境（Land of Ooo），沿着旅途陆续遇上剧中其他的主要角色：泡泡糖公主（Princess Bubblegum）、寒冰王（The Ice King）以及马瑟琳（Marceline the Vampire Queen）。