Phineas and Ferb head to the Tri-State Area's annual sci-fi and fantasy convention to meet their hero, special effects guru Clive Addison. Their plan gets sidetracked when they're swept into a duel between the fantasy fans and the sci-fi geeks. Meanwhile, Candace tries to keep secret that she's a fan of Ducky Momo, another convention staple. Across the convention hall, Dr. Doofenshmirtz has taken television executive Jeff McGarland hostage so he can pitch him a show he's developed, "Doof 'n' Puss."