teen drama television series 1990s Canadian science fiction television series 1990s Canadian teen drama television series 1998 American television series debuts 1998 Canadian television series debuts 1999 American television series endings 1999 Canadian television series endings Alien invasions in television American children's action television series American children's adventure television series American children's fantasy television series American children's science fiction television series American television shows based on children's books Canadian children's action television series Canadian children's adventure television series Canadian children's fantasy television series Canadian children's science fiction television series Canadian television shows based on children's books English-language television shows YTV (Canadian TV channel) original programming Television shows based on American novels Television shows filmed in Toronto Works based on Animorphs Television series about teenagers Television series about extraterrestrial life Television series about shapeshifting