The actress will play Adalind's fellow Hexenbiest mother, Catherine, in an episode set to air later this season. Hexenbiests are witch-like creatures who usually work for royalty, and are extremely loyal. In human form, they are extremely beautiful and all the Hexenbiests seen on the show thus far have been female lawyers.
Best known for her longtime role on One Life to Live, Tuck played vampire-human liaison Nan Flanagan on the HBO vampire drama before she was staked in Season 4. She also guest-starred on Castle earlier this season.
Grimm airs Fridays at 9/8c on NBC.