Now You See Me~Margaret Murphy

the long version

When Megan Ward goes missing, suspicion falls on the stalker seen outside her house. The police would love it to be so simple, but the closer they look the more mysterious Megan herself becomes. They find no photos, no passport, no family or friends from an earlier life, only the corrupted computer files in Megan's strangely impersonal room. Meanwhile Patrick Doran, owner of Safe Hands Security, is living his own nightmare. A hacker has breached his computer network, where he thought he had safely buried his past. Then Megan's landlady is murdered - and the shadowy Megan re-emerges. The woman who doesn't exist becomes very real, very elusive and very dangerous.