Lady Dedlock wears a cold, haughty mask because she has a secret to hide: a great passion that led to an illegitimate child and heartbreak. Until we discover this secret, Lady Dedlock seems to be little more than an unpleasant member of high society, bored with absolutely everything and unwilling to be bothered by anyone, including her husband, Sir Leicester. Lady Dedlock seems not to care about or have any interest in the world around her. When we discover her secret, however, we know all this to be false. Far from being disengaged from the world because of snobbery, Lady Dedlock keeps the world at arm’s length out of fear and pain: fear that her secret will be revealed and bring the whole Dedlock family tumbling down, and pain from events from her past. Regal, stone-cold Lady Dedlock, watched and talked about by the public as though she is greater than life, has a very human, very messy past that throbs beneath her unshakeable exterior.
When Lady Dedlock finds that her past is catching up with her, she begins acting in a way that seems shockingly inappropriate for a woman of the Dedlock name. For example, she disguises herself and asks Jo, a street urchin, to show her the burial ground of the dead lodger, who we eventually learn was her former lover. When Esther is sick, Lady Dedlock disguises herself again and tries to find out information about her by going to the brickmaker’s cottage. And when she fears her secret is about to come out, she leaves her jewels and money behind and flees, eventually dying on the street. Lady Dedlock, who seems at first to have no passion, ultimately shows herself to be so passionate that she will die to protect those she loves.