Familiar characters created by Sir Arthur Conan Doyle gain a new lease of life on the streets of Victorian London in a British crime drama created by Tom Bidwell. Sherlock Holmes (Henry Lloyd-Hughes) and his sinister business partner Dr John Watson (Royce Pierreson) are pitted against dark forces in the capital. They manipulate a gang of troubled street urchins led by 17-year-old Bea (Thaddea Graham) into solving crimes with a disturbing supernatural edge. Bea, her younger sister Jessie (Darci Shaw) and other members of the Irregulars - Billy (Jojo Macari), Leo (Harrison Osterfield) and Spike (McKell David) - are drawn into a diabolical plot that extends far beyond the city limits. The teenagers will test their courage and resourcefulness to the limit to save the world from destruction.