The series stars Sarah Michelle Gellar as estranged twins Bridget and Siobhan. Bridget is a recovering addict on the run from some unsavory people, who takes on her presumed-dead sister's identity as a last resort.
Dohring, best known for his role on Veronica Mars, will play Mr. Carpenter, a teacher at the new public high school that Siobhan's step-daughter Juliet (Zoey Deutch) is forced to attend. Though Juliet is quite the wild-child, Mr. Carpenter sees potential in her when no one else does. Entertainment Weekly first reported the news.
Ringer premieres Tuesday, Sept. 13 at 9/8c on the CW.