Broken (Women of the Otherworld)

When half-demon Xavier calls in the favour Elena owes him, it seems easy enough, steal Jack the Rippers From Hell letter away from a Toronto collector who had himself stolen it from the Ripper evidence boxes. But nothing in the supernatural world is ever as simple as it seems. Elena accidentally triggers a spell placed on the letter, and opens a dimensional portal into Victorian London, releasing zombies, disease, and maybe a notorious serial killer himself.