Character: Genevieve Teague. She's a ruthless, Machiavellian player, a manipulative mother, and obsessed with finding the Kryptonian stones and willing to do anything to get them. Appropriately enough, she's stabbed to death with one of them.
Whose Mom? Jason Teague (season 4 regular Jensen Ackles).
Why She Looks Familiar: Jane Seymour was Dr. Quinn, Medicine Woman (1993-98), Solitaire in Live and Let Die, and Serina on Battlestar Galactica (1978).
Fun scene: Genevieve plays coy with her son's suspicions that she engineered his meeting with Lana Lang: "I just want you to know, Jason, that I'm really glad that you're happy. Lana is... an enchanting girl. I can see why you moved to the middle of nowhere to be with her. She's... she's special. I knew you'd meet someone like her one day."