Penelope Ann Miller, Colin Ford, and Shaun Brown have joined the cast of “Monster: The Jeffrey Dahmer Story” opposite Evan Peters, Niecy Nash, and Richard Jenkins. #Monster  

Michael Learned has officially joined the cast of “Monster: The Jeffrey Dahmer Story” as Catherine Dahmer, the serial killer’s grandmother. #Monster  

Molly Ringwald has joined the cast of Ryan Murphy’s “Monster: The Jeffrey Dahmer Story.” She portrays Shari Dahmer, Jeffrey’s stepmother.