It's About Time!, Dude, We're Gettin' the Band Back Together!

Phineas and Ferb find a time machine at a museum and travel back to the Jurassic Age. Meanwhile, Perry is sad when Doofenshmirtz replaces him with a new nemesis, Peter the Panda, so he confides in a relationship talk-show host.
The boys locate their parents' favorite band, Love Handel, to perform a reunion concert in the backyard to make up Dad forgetting his wedding anniversary. Meanwhile, Doofenshmirtz plans a surprise birthday party for his daughter, Vanessa.