The two texts are related through the central character of Mrs. Rochester, who appears in Bronte's original Jane Eyre as a maddened character who is locked up by her husband in the attic of Thornfield Hall. The way she is described makes her appear to be more animal than human, and the story that Mr. Rochester tells Jane about her and her mental instability. Note how she is described in the following quote, when Jane is finally brought face to face with the first wife of the man she was hoping to marry:
She was a big woman, in stature almost equalling her husband, and corpulent besides: she showed virile force in the contest...
The adjectives applied to her are less than flattering, described as "corpulent" and "big." However, many critics have been less than satisfied with the picture that is painted of Mrs. Rochester in this novel, and they argue that as the reader never hears from Mrs. Rochester herself, we are presented with an extremely partial view of her. In particular, feminist critics and postcolonial critics find the fact that Mrs. Rochester was locked up in the attic yet still alive very poignant, especially when it is considered that there are actually a number of links between the character of Jane Eyre and, as some believe Mrs. Rochester to be, her alter ego.
Wide Sargasso Sea therefore is a revisionist work that tells the story of Mrs. Rochester but from her point of view. As becomes clear very quickly, what Rhys does in this novel is to engage the reader's sympathy for Mrs. Rochester in a way that Bronte's original work fails to do. Note, for example, the following quote:
There is no looking glass here and I don't know what I am like now. I remember watching myself brush my hair and how my eyes looked back at me. The girl I saw was myself yet not quite myself. Long ago when I was a child and very lonely I tried to kiss her. But the glass was between us—hard, cold and misted over with my breath. Now they have taken everything away. What am I doing in this place and who am I?
The rhetorical question at the end, and the lucidity that the character of Antoinette seems to display is very moving, as is the depiction of the difference between herself and the image of herself in the mirror. Note how she tries to unite the two split halves of her identity, but she is prevented from doing so. The big link between these two works, therefore, is the character of Mrs. Rochester.