Dohring was a cast member of the short-lived, but beloved series "Veronica Mars," which drew comparisons to Gellar's "Buffy the Vampire Slayer" for its plucky blonde, evil-battling heroine, snappy dialogue and quirky supporting characters.
"Buffy" alum Charisma Carpenter and Alyson Hannigan also had recurring roles on "Veronica Mars."
EW.com said Dohring will play a teacher at the new school attended by Juliet, the stepdaughter of Manhattan socialite Siobhan Martin, on "Ringer."
Newcomer Zoey Deutch, who is actress Lea Thompson's daughter, plays Juliet and Nestor Carbonell from "Lost" will play an FBI agent on the thriller series, which is to premiere Sept. 13.
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