Why is Thomas Ricoletti surprised to see his wife dressed in her old wedding gown? Because, just a few hours before, she took her own life and now her ghost appears to be prowling the streets with a thirst for revenge. Sherlock Holmes (Benedict Cumberbatch) and Dr. John Watson (Martin Freeman) return in this modern retelling of the Arthur Conan Doyle stories, but this time out, the two find themselves in 1890s London.