Phineas, Ferb, Perry the Platypus, and Dr. Doofenshmirtz are back for an interstellar adventure in this chapter book based on the new Disney+ original movie. When Candace is abducted by aliens, Phineas and Ferb have to team up with Dr. Doofenshmirtz to get her back . . . but what if she doesn’t want to return to Earth?