Previous Fringe spoilers hinted that fans would eventually meet Peter's mother and Walter's ex-wife.
Now, Michael Ausiello has confirmed that this character will debut in early 2010 - and she'll be played by Irish actress Orla Brady.
As the character Claire Stark, Brady appeared for a quartet of Shark episodes back in 2007. That's been her only major role on U.S. television. Until now.
No word yet on how many episodes the actress will appear in as Mrs. Bishop, who previous casting notices described as "strong, smart, and likable."