The adventure of the long lost lover

So far, I have only written one chapter. Monsieur Pierre Defarge comes to see the famous detective at 221B with a unique case. His long lost lover has suddenly written to him, wishing to renew relationships but M. Defarge is convinced the document is a fraud. Can Holmes advise Defarge on the right course of action, will the drama that ensues reflect on Holmes' poor judgement?