The Hidden Thread was discovered by competition winners because they realised that the third letter of each diary page entered spelt out the victim’s name. Annie used the third letter because her husband always used to call her 3xalady.

Also in one of the diary entries, Annie wrote “must fill in Blog”. The detective wrote beside this entry that the school didn’t have a blog. Annie had created a blog and her user name was 3xalady. When competition entrants went on to 3xalady.co.uk, they found a competition entry form, Annie’s diary pages with the third letter highlighted in red and also a confession for each of Annie’s murders.