Muriel Chanler was the wife of John Chanler. She came to her ex-fiance Dr. Warthrop after John went missing. She was eventually killed by John after he became psychotic.
John Chanler was Muriel's husband.
Dr. Warthrop was Muriel's ex-fiance. Although they broke up, she still loved and trusted him as is evident when she came to him for help after John went missing.