Hannigan will play brain surgeon Dr. Ann Possible, also known as Mom Possible, the mother of the titular heroine.
Connie Ray, Todd Stashwick, Taylor Ortega, Ciara Wilson and Erika Tham will co-star in the story about a high-school girl who saves the world from villains with the help of her best friend Ron Stoppable.
Newcomer Sadie Stanley will play Kim and The Goldbergs star Sean Giambrone will play Ron.
The comedy-adventure is scheduled to air in 2019.
More #KimPossible casting news! @alydenisof will play Mom Possible and Connie Ray will play Nana Possible. Also joining the cast are @ToddStashwick as Drakken, @taylor_ortega as Shego, @Ciarawilsonxo as Athena and @ErikaTham as Bonnie. pic.twitter.com/X0INS7cVBJ— Disney Channel (@DisneyChannel) May 25, 2018