What is the main conflict in Lost by Gregory Maguire?

Winifred or Winnie is writing a novel about a young woman named Wendy Pritzke who is haunted by the ghost of Jack the Ripper. Winnie plans to stay with her step-cousin and good friend, John Comester in London while she researches famed Jack the Ripper tourist spots for the novel. Although Winnie proves to be a bit of a curmudgeon who holds most people at arm's length, she clearly views John as her one true friend and is quit excited to see him. When Winnie arrives in London however, John is nowhere to be found.