Morella Fell is the sister of Carmilla Fell. She was one of the actors during the Phantasmagoria and her act was known as the "The Fell Sister's Cabinet".

The performance involves her sitting across from her sister in the cabinet with a knot tied between them. The cabinet is closed and a gong is sounded. When the cabinet is opened again, the sisters switched places.

Morella Fell killed Simon Hunt when he was trying to show her act was fake. She together with Simon inside the cabinet with a dagger between their arms. Then when the box was closed, she was able to remove the knot since the knot was a slip knot and stabbed Simon.