Words cannot describe how awful this sequel is. I often wonder what compelled the author to make some of the choices she did when writing this. Did she even read the original novella by Henry James? After the events in TOTS, Flora goes to live with her uncle (his reason for lack of parental care in the original was simply wasted and predictable here) who actually cares about her in this. She's 18 now and engaged to marry some rich man who is a paragon to society. However, she is haunted by her dead brother (who for whatever reason appears to her as an adult wearing a soldier's uniform...OK then). Then we have Mrs. Grose who still lives at Bly even though no one else lives there. The governess (the author decided to give her a name) has just been released from a sanitarium, makes her way back to Bly where (and this is the part to really laugh at) Mrs. Grose and she decide to contact Quentin's spirit (HOLD up - since when did Mrs. Grose believe her in the first place? *face/palm) and end up becoming possessed by him.
If you want my advice, read the original because the sequel just has nothing to offer.