Plummer won the statuette for his work in "Beginners." Spencer picked up the prize for her performance in "The Help."
"I just can't tell you what fun I've had being a member of the world's second oldest profession," Plummer quipped as he accepted his award. "Actors are gregarious and wacky, are they not? And I love them dearly and when they honor you, it's like being lit by the Holy Grail. Thank you, thank you, thank you."
"This means so much to me, coming from you, SAG," a tearful Spencer said as she collected her statuette. "It was really a privilege to work on a film that gave a voice to so many women who made it possible for me to be standing here tonight. These women represented our mothers and grandmothers and it was their courage and them facing the challenges they faced every day and living their lives with dignity and grace. I thank you. By honoring me, you honor them."
Celebrity Families of 2014 [PHOTOS]